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 <[email protected]> 13 * 14 * Written or modified by: 15 * Randall Stewart <[email protected]> 16 * Ken Morneau <[email protected]> 17 * Qiaobing Xie <[email protected]> 18 * La Monte H.P. Yarroll <[email protected]> 19 * Karl Knutson <[email protected]> 20 * Jon Grimm <[email protected]> 21 * Xingang Guo <[email protected]> 22 * Hui Huang <[email protected]> 23 * Sridhar Samudrala <[email protected]> 24 * Daisy Chang <[email protected]> 25 * Dajiang Zhang <[email protected]> 26 * Ardelle Fan <[email protected]> 27 * Ryan Layer <[email protected]> 28 * Anup Pemmaiah <[email protected]> 29 * Kevin Gao <[email protected]> 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 __u32 probe_interval; 181 182 __be16 udp_port; 183 __be16 encap_port; 184 185 /* This is the max_retrans value for new associations. */ 186 __u16 pathmaxrxt; 187 188 __u32 flowlabel; 189 __u8 dscp; 190 191 __u16 pf_retrans; 192 __u16 ps_retrans; 193 194 /* The initial Path MTU to use for new associations. */ 195 __u32 pathmtu; 196 197 /* The default SACK delay timeout for new associations. */ 198 __u32 sackdelay; 199 __u32 sackfreq; 200 201 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 202 __u32 param_flags; 203 204 __u32 default_ss; 205 206 struct sctp_rtoinfo rtoinfo; 207 struct sctp_paddrparams paddrparam; 208 struct sctp_assocparams assocparams; 209 210 /* 211 * These two structures must be grouped together for the usercopy 212 * whitelist region. 213 */ 214 __u16 subscribe; 215 struct sctp_initmsg initmsg; 216 217 int user_frag; 218 219 __u32 autoclose; 220 __u32 adaptation_ind; 221 __u32 pd_point; 222 __u16 nodelay:1, 223 pf_expose:2, 224 reuse:1, 225 disable_fragments:1, 226 v4mapped:1, 227 frag_interleave:1, 228 recvrcvinfo:1, 229 recvnxtinfo:1, 230 data_ready_signalled:1; 231 232 atomic_t pd_mode; 233 234 /* Fields after this point will be skipped on copies, like on accept 235 * and peeloff operations 236 */ 237 238 /* Receive to here while partial delivery is in effect. */ 239 struct sk_buff_head pd_lobby; 240 241 struct list_head auto_asconf_list; 242 int do_auto_asconf; 243 }; 244 245 static inline struct sctp_sock *sctp_sk(const struct sock *sk) 246 { 247 return (struct sctp_sock *)sk; 248 } 249 250 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp) 251 { 252 return (struct sock *)sp; 253 } 254 255 #if IS_ENABLED(CONFIG_IPV6) 256 struct sctp6_sock { 257 struct sctp_sock sctp; 258 struct ipv6_pinfo inet6; 259 }; 260 #endif /* CONFIG_IPV6 */ 261 262 263 /* This is our APPLICATION-SPECIFIC state cookie. 264 * THIS IS NOT DICTATED BY THE SPECIFICATION. 265 */ 266 /* These are the parts of an association which we send in the cookie. 267 * Most of these are straight out of: 268 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB) 269 * 270 */ 271 272 struct sctp_cookie { 273 274 /* My : Tag expected in every inbound packet and sent 275 * Verification: in the INIT or INIT ACK chunk. 276 * Tag : 277 */ 278 __u32 my_vtag; 279 280 /* Peer's : Tag expected in every outbound packet except 281 * Verification: in the INIT chunk. 282 * Tag : 283 */ 284 __u32 peer_vtag; 285 286 /* The rest of these are not from the spec, but really need to 287 * be in the cookie. 288 */ 289 290 /* My Tie Tag : Assist in discovering a restarting association. */ 291 __u32 my_ttag; 292 293 /* Peer's Tie Tag: Assist in discovering a restarting association. */ 294 __u32 peer_ttag; 295 296 /* When does this cookie expire? */ 297 ktime_t expiration; 298 299 /* Number of inbound/outbound streams which are set 300 * and negotiated during the INIT process. 301 */ 302 __u16 sinit_num_ostreams; 303 __u16 sinit_max_instreams; 304 305 /* This is the first sequence number I used. */ 306 __u32 initial_tsn; 307 308 /* This holds the originating address of the INIT packet. */ 309 union sctp_addr peer_addr; 310 311 /* IG Section 2.35.3 312 * Include the source port of the INIT-ACK 313 */ 314 __u16 my_port; 315 316 __u8 prsctp_capable; 317 318 /* Padding for future use */ 319 __u8 padding; 320 321 __u32 adaptation_ind; 322 323 __u8 auth_random[sizeof(struct sctp_paramhdr) + 324 SCTP_AUTH_RANDOM_LENGTH]; 325 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2]; 326 __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS]; 327 328 /* This is a shim for my peer's INIT packet, followed by 329 * a copy of the raw address list of the association. 330 * The length of the raw address list is saved in the 331 * raw_addr_list_len field, which will be used at the time when 332 * the association TCB is re-constructed from the cookie. 333 */ 334 __u32 raw_addr_list_len; 335 struct sctp_init_chunk peer_init[]; 336 }; 337 338 339 /* The format of our cookie that we send to our peer. */ 340 struct sctp_signed_cookie { 341 __u8 signature[SCTP_SECRET_SIZE]; 342 __u32 __pad; /* force sctp_cookie alignment to 64 bits */ 343 struct sctp_cookie c; 344 } __packed; 345 346 /* This is another convenience type to allocate memory for address 347 * params for the maximum size and pass such structures around 348 * internally. 349 */ 350 union sctp_addr_param { 351 struct sctp_paramhdr p; 352 struct sctp_ipv4addr_param v4; 353 struct sctp_ipv6addr_param v6; 354 }; 355 356 /* A convenience type to allow walking through the various 357 * parameters and avoid casting all over the place. 358 */ 359 union sctp_params { 360 void *v; 361 struct sctp_paramhdr *p; 362 struct sctp_cookie_preserve_param *life; 363 struct sctp_hostname_param *dns; 364 struct sctp_cookie_param *cookie; 365 struct sctp_supported_addrs_param *sat; 366 struct sctp_ipv4addr_param *v4; 367 struct sctp_ipv6addr_param *v6; 368 union sctp_addr_param *addr; 369 struct sctp_adaptation_ind_param *aind; 370 struct sctp_supported_ext_param *ext; 371 struct sctp_random_param *random; 372 struct sctp_chunks_param *chunks; 373 struct sctp_hmac_algo_param *hmac_algo; 374 struct sctp_addip_param *addip; 375 }; 376 377 /* RFC 2960. Section 3.3.5 Heartbeat. 378 * Heartbeat Information: variable length 379 * The Sender-specific Heartbeat Info field should normally include 380 * information about the sender's current time when this HEARTBEAT 381 * chunk is sent and the destination transport address to which this 382 * HEARTBEAT is sent (see Section 8.3). 383 */ 384 struct sctp_sender_hb_info { 385 struct sctp_paramhdr param_hdr; 386 union sctp_addr daddr; 387 unsigned long sent_at; 388 __u64 hb_nonce; 389 __u32 probe_size; 390 }; 391 392 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt, 393 gfp_t gfp); 394 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid); 395 void sctp_stream_free(struct sctp_stream *stream); 396 void sctp_stream_clear(struct sctp_stream *stream); 397 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new); 398 399 /* What is the current SSN number for this stream? */ 400 #define sctp_ssn_peek(stream, type, sid) \ 401 (sctp_stream_##type((stream), (sid))->ssn) 402 403 /* Return the next SSN number for this stream. */ 404 #define sctp_ssn_next(stream, type, sid) \ 405 (sctp_stream_##type((stream), (sid))->ssn++) 406 407 /* Skip over this ssn and all below. */ 408 #define sctp_ssn_skip(stream, type, sid, ssn) \ 409 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1) 410 411 /* What is the current MID number for this stream? */ 412 #define sctp_mid_peek(stream, type, sid) \ 413 (sctp_stream_##type((stream), (sid))->mid) 414 415 /* Return the next MID number for this stream. */ 416 #define sctp_mid_next(stream, type, sid) \ 417 (sctp_stream_##type((stream), (sid))->mid++) 418 419 /* Skip over this mid and all below. */ 420 #define sctp_mid_skip(stream, type, sid, mid) \ 421 (sctp_stream_##type((stream), (sid))->mid = mid + 1) 422 423 /* What is the current MID_uo number for this stream? */ 424 #define sctp_mid_uo_peek(stream, type, sid) \ 425 (sctp_stream_##type((stream), (sid))->mid_uo) 426 427 /* Return the next MID_uo number for this stream. */ 428 #define sctp_mid_uo_next(stream, type, sid) \ 429 (sctp_stream_##type((stream), (sid))->mid_uo++) 430 431 /* 432 * Pointers to address related SCTP functions. 433 * (i.e. things that depend on the address family.) 434 */ 435 struct sctp_af { 436 int (*sctp_xmit) (struct sk_buff *skb, 437 struct sctp_transport *); 438 int (*setsockopt) (struct sock *sk, 439 int level, 440 int optname, 441 sockptr_t optval, 442 unsigned int optlen); 443 int (*getsockopt) (struct sock *sk, 444 int level, 445 int optname, 446 char __user *optval, 447 int __user *optlen); 448 void (*get_dst) (struct sctp_transport *t, 449 union sctp_addr *saddr, 450 struct flowi *fl, 451 struct sock *sk); 452 void (*get_saddr) (struct sctp_sock *sk, 453 struct sctp_transport *t, 454 struct flowi *fl); 455 void (*copy_addrlist) (struct list_head *, 456 struct net_device *); 457 int (*cmp_addr) (const union sctp_addr *addr1, 458 const union sctp_addr *addr2); 459 void (*addr_copy) (union sctp_addr *dst, 460 union sctp_addr *src); 461 void (*from_skb) (union sctp_addr *, 462 struct sk_buff *skb, 463 int saddr); 464 void (*from_sk) (union sctp_addr *, 465 struct sock *sk); 466 void (*from_addr_param) (union sctp_addr *, 467 union sctp_addr_param *, 468 __be16 port, int iif); 469 int (*to_addr_param) (const union sctp_addr *, 470 union sctp_addr_param *); 471 int (*addr_valid) (union sctp_addr *, 472 struct sctp_sock *, 473 const struct sk_buff *); 474 enum sctp_scope (*scope)(union sctp_addr *); 475 void (*inaddr_any) (union sctp_addr *, __be16); 476 int (*is_any) (const union sctp_addr *); 477 int (*available) (union sctp_addr *, 478 struct sctp_sock *); 479 int (*skb_iif) (const struct sk_buff *sk); 480 int (*is_ce) (const struct sk_buff *sk); 481 void (*seq_dump_addr)(struct seq_file *seq, 482 union sctp_addr *addr); 483 void (*ecn_capable)(struct sock *sk); 484 __u16 net_header_len; 485 int sockaddr_len; 486 int (*ip_options_len)(struct sock *sk); 487 sa_family_t sa_family; 488 struct list_head list; 489 }; 490 491 struct sctp_af *sctp_get_af_specific(sa_family_t); 492 int sctp_register_af(struct sctp_af *); 493 494 /* Protocol family functions. */ 495 struct sctp_pf { 496 void (*event_msgname)(struct sctp_ulpevent *, char *, int *); 497 void (*skb_msgname) (struct sk_buff *, char *, int *); 498 int (*af_supported) (sa_family_t, struct sctp_sock *); 499 int (*cmp_addr) (const union sctp_addr *, 500 const union sctp_addr *, 501 struct sctp_sock *); 502 int (*bind_verify) (struct sctp_sock *, union sctp_addr *); 503 int (*send_verify) (struct sctp_sock *, union sctp_addr *); 504 int (*supported_addrs)(const struct sctp_sock *, __be16 *); 505 struct sock *(*create_accept_sk) (struct sock *sk, 506 struct sctp_association *asoc, 507 bool kern); 508 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr); 509 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk); 510 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk); 511 void (*copy_ip_options)(struct sock *sk, struct sock *newsk); 512 struct sctp_af *af; 513 }; 514 515 516 /* Structure to track chunk fragments that have been acked, but peer 517 * fragments of the same message have not. 518 */ 519 struct sctp_datamsg { 520 /* Chunks waiting to be submitted to lower layer. */ 521 struct list_head chunks; 522 /* Reference counting. */ 523 refcount_t refcnt; 524 /* When is this message no longer interesting to the peer? */ 525 unsigned long expires_at; 526 /* Did the messenge fail to send? */ 527 int send_error; 528 u8 send_failed:1, 529 can_delay:1, /* should this message be Nagle delayed */ 530 abandoned:1; /* should this message be abandoned */ 531 }; 532 533 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *, 534 struct sctp_sndrcvinfo *, 535 struct iov_iter *); 536 void sctp_datamsg_free(struct sctp_datamsg *); 537 void sctp_datamsg_put(struct sctp_datamsg *); 538 void sctp_chunk_fail(struct sctp_chunk *, int error); 539 int sctp_chunk_abandoned(struct sctp_chunk *); 540 541 /* RFC2960 1.4 Key Terms 542 * 543 * o Chunk: A unit of information within an SCTP packet, consisting of 544 * a chunk header and chunk-specific content. 545 * 546 * As a matter of convenience, we remember the SCTP common header for 547 * each chunk as well as a few other header pointers... 548 */ 549 struct sctp_chunk { 550 struct list_head list; 551 552 refcount_t refcnt; 553 554 /* How many times this chunk have been sent, for prsctp RTX policy */ 555 int sent_count; 556 557 union { 558 /* This is our link to the per-transport transmitted list. */ 559 struct list_head transmitted_list; 560 /* List in specific stream outq */ 561 struct list_head stream_list; 562 }; 563 564 /* This field is used by chunks that hold fragmented data. 565 * For the first fragment this is the list that holds the rest of 566 * fragments. For the remaining fragments, this is the link to the 567 * frag_list maintained in the first fragment. 568 */ 569 struct list_head frag_list; 570 571 /* This points to the sk_buff containing the actual data. */ 572 struct sk_buff *skb; 573 574 union { 575 /* In case of GSO packets, this will store the head one */ 576 struct sk_buff *head_skb; 577 /* In case of auth enabled, this will point to the shkey */ 578 struct sctp_shared_key *shkey; 579 }; 580 581 /* These are the SCTP headers by reverse order in a packet. 582 * Note that some of these may happen more than once. In that 583 * case, we point at the "current" one, whatever that means 584 * for that level of header. 585 */ 586 587 /* We point this at the FIRST TLV parameter to chunk_hdr. */ 588 union sctp_params param_hdr; 589 union { 590 __u8 *v; 591 struct sctp_datahdr *data_hdr; 592 struct sctp_inithdr *init_hdr; 593 struct sctp_sackhdr *sack_hdr; 594 struct sctp_heartbeathdr *hb_hdr; 595 struct sctp_sender_hb_info *hbs_hdr; 596 struct sctp_shutdownhdr *shutdown_hdr; 597 struct sctp_signed_cookie *cookie_hdr; 598 struct sctp_ecnehdr *ecne_hdr; 599 struct sctp_cwrhdr *ecn_cwr_hdr; 600 struct sctp_errhdr *err_hdr; 601 struct sctp_addiphdr *addip_hdr; 602 struct sctp_fwdtsn_hdr *fwdtsn_hdr; 603 struct sctp_authhdr *auth_hdr; 604 struct sctp_idatahdr *idata_hdr; 605 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr; 606 } subh; 607 608 __u8 *chunk_end; 609 610 struct sctp_chunkhdr *chunk_hdr; 611 struct sctphdr *sctp_hdr; 612 613 /* This needs to be recoverable for SCTP_SEND_FAILED events. */ 614 struct sctp_sndrcvinfo sinfo; 615 616 /* Which association does this belong to? */ 617 struct sctp_association *asoc; 618 619 /* What endpoint received this chunk? */ 620 struct sctp_ep_common *rcvr; 621 622 /* We fill this in if we are calculating RTT. */ 623 unsigned long sent_at; 624 625 /* What is the origin IP address for this chunk? */ 626 union sctp_addr source; 627 /* Destination address for this chunk. */ 628 union sctp_addr dest; 629 630 /* For outbound message, track all fragments for SEND_FAILED. */ 631 struct sctp_datamsg *msg; 632 633 /* For an inbound chunk, this tells us where it came from. 634 * For an outbound chunk, it tells us where we'd like it to 635 * go. It is NULL if we have no preference. 636 */ 637 struct sctp_transport *transport; 638 639 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO 640 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH 641 * spec violates the principle premis that all chunks are processed 642 * in order. 643 */ 644 struct sk_buff *auth_chunk; 645 646 #define SCTP_CAN_FRTX 0x0 647 #define SCTP_NEED_FRTX 0x1 648 #define SCTP_DONT_FRTX 0x2 649 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */ 650 has_tsn:1, /* Does this chunk have a TSN yet? */ 651 has_ssn:1, /* Does this chunk have a SSN yet? */ 652 #define has_mid has_ssn 653 singleton:1, /* Only chunk in the packet? */ 654 end_of_packet:1, /* Last chunk in the packet? */ 655 ecn_ce_done:1, /* Have we processed the ECN CE bit? */ 656 pdiscard:1, /* Discard the whole packet now? */ 657 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */ 658 data_accepted:1, /* At least 1 chunk accepted */ 659 auth:1, /* IN: was auth'ed | OUT: needs auth */ 660 has_asconf:1, /* IN: have seen an asconf before */ 661 pmtu_probe:1, /* Used by PLPMTUD, can be set in s HB chunk */ 662 tsn_missing_report:2, /* Data chunk missing counter. */ 663 fast_retransmit:2; /* Is this chunk fast retransmitted? */ 664 }; 665 666 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1) 667 void sctp_chunk_hold(struct sctp_chunk *); 668 void sctp_chunk_put(struct sctp_chunk *); 669 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len, 670 struct iov_iter *from); 671 void sctp_chunk_free(struct sctp_chunk *); 672 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data); 673 struct sctp_chunk *sctp_chunkify(struct sk_buff *, 674 const struct sctp_association *, 675 struct sock *, gfp_t gfp); 676 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *, 677 union sctp_addr *); 678 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk); 679 680 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch) 681 { 682 return ntohs(ch->subh.data_hdr->stream); 683 } 684 685 enum { 686 SCTP_ADDR_NEW, /* new address added to assoc/ep */ 687 SCTP_ADDR_SRC, /* address can be used as source */ 688 SCTP_ADDR_DEL, /* address about to be deleted */ 689 }; 690 691 /* This is a structure for holding either an IPv6 or an IPv4 address. */ 692 struct sctp_sockaddr_entry { 693 struct list_head list; 694 struct rcu_head rcu; 695 union sctp_addr a; 696 __u8 state; 697 __u8 valid; 698 }; 699 700 #define SCTP_ADDRESS_TICK_DELAY 500 701 702 /* This structure holds lists of chunks as we are assembling for 703 * transmission. 704 */ 705 struct sctp_packet { 706 /* These are the SCTP header values (host order) for the packet. */ 707 __u16 source_port; 708 __u16 destination_port; 709 __u32 vtag; 710 711 /* This contains the payload chunks. */ 712 struct list_head chunk_list; 713 714 /* This is the overhead of the sctp and ip headers. */ 715 size_t overhead; 716 /* This is the total size of all chunks INCLUDING padding. */ 717 size_t size; 718 /* This is the maximum size this packet may have */ 719 size_t max_size; 720 721 /* The packet is destined for this transport address. 722 * The function we finally use to pass down to the next lower 723 * layer lives in the transport structure. 724 */ 725 struct sctp_transport *transport; 726 727 /* pointer to the auth chunk for this packet */ 728 struct sctp_chunk *auth; 729 730 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */ 731 has_sack:1, /* This packet contains a SACK chunk. */ 732 has_auth:1, /* This packet contains an AUTH chunk */ 733 has_data:1, /* This packet contains at least 1 DATA chunk */ 734 ipfragok:1; /* So let ip fragment this packet */ 735 }; 736 737 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *, 738 __u16 sport, __u16 dport); 739 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int); 740 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet, 741 struct sctp_chunk *chunk, 742 int one_packet, gfp_t gfp); 743 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet, 744 struct sctp_chunk *chunk); 745 int sctp_packet_transmit(struct sctp_packet *, gfp_t); 746 void sctp_packet_free(struct sctp_packet *); 747 748 static inline int sctp_packet_empty(struct sctp_packet *packet) 749 { 750 return packet->size == packet->overhead; 751 } 752 753 /* This represents a remote transport address. 754 * For local transport addresses, we just use union sctp_addr. 755 * 756 * RFC2960 Section 1.4 Key Terms 757 * 758 * o Transport address: A Transport Address is traditionally defined 759 * by Network Layer address, Transport Layer protocol and Transport 760 * Layer port number. In the case of SCTP running over IP, a 761 * transport address is defined by the combination of an IP address 762 * and an SCTP port number (where SCTP is the Transport protocol). 763 * 764 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control 765 * 766 * o The sender keeps a separate congestion control parameter set for 767 * each of the destination addresses it can send to (not each 768 * source-destination pair but for each destination). The parameters 769 * should decay if the address is not used for a long enough time 770 * period. 771 * 772 */ 773 struct sctp_transport { 774 /* A list of transports. */ 775 struct list_head transports; 776 struct rhlist_head node; 777 778 /* Reference counting. */ 779 refcount_t refcnt; 780 /* RTO-Pending : A flag used to track if one of the DATA 781 * chunks sent to this address is currently being 782 * used to compute a RTT. If this flag is 0, 783 * the next DATA chunk sent to this destination 784 * should be used to compute a RTT and this flag 785 * should be set. Every time the RTT 786 * calculation completes (i.e. the DATA chunk 787 * is SACK'd) clear this flag. 788 */ 789 __u32 rto_pending:1, 790 791 /* 792 * hb_sent : a flag that signals that we have a pending 793 * heartbeat. 794 */ 795 hb_sent:1, 796 797 /* Is the Path MTU update pending on this tranport */ 798 pmtu_pending:1, 799 800 dst_pending_confirm:1, /* need to confirm neighbour */ 801 802 /* Has this transport moved the ctsn since we last sacked */ 803 sack_generation:1; 804 u32 dst_cookie; 805 806 struct flowi fl; 807 808 /* This is the peer's IP address and port. */ 809 union sctp_addr ipaddr; 810 811 /* These are the functions we call to handle LLP stuff. */ 812 struct sctp_af *af_specific; 813 814 /* Which association do we belong to? */ 815 struct sctp_association *asoc; 816 817 /* RFC2960 818 * 819 * 12.3 Per Transport Address Data 820 * 821 * For each destination transport address in the peer's 822 * address list derived from the INIT or INIT ACK chunk, a 823 * number of data elements needs to be maintained including: 824 */ 825 /* RTO : The current retransmission timeout value. */ 826 unsigned long rto; 827 828 __u32 rtt; /* This is the most recent RTT. */ 829 830 /* RTTVAR : The current RTT variation. */ 831 __u32 rttvar; 832 833 /* SRTT : The current smoothed round trip time. */ 834 __u32 srtt; 835 836 /* 837 * These are the congestion stats. 838 */ 839 /* cwnd : The current congestion window. */ 840 __u32 cwnd; /* This is the actual cwnd. */ 841 842 /* ssthresh : The current slow start threshold value. */ 843 __u32 ssthresh; 844 845 /* partial : The tracking method for increase of cwnd when in 846 * bytes acked : congestion avoidance mode (see Section 6.2.2) 847 */ 848 __u32 partial_bytes_acked; 849 850 /* Data that has been sent, but not acknowledged. */ 851 __u32 flight_size; 852 853 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */ 854 855 /* Destination */ 856 struct dst_entry *dst; 857 /* Source address. */ 858 union sctp_addr saddr; 859 860 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 861 * the destination address every heartbeat interval. 862 */ 863 unsigned long hbinterval; 864 unsigned long probe_interval; 865 866 /* SACK delay timeout */ 867 unsigned long sackdelay; 868 __u32 sackfreq; 869 870 atomic_t mtu_info; 871 872 /* When was the last time that we heard from this transport? We use 873 * this to pick new active and retran paths. 874 */ 875 ktime_t last_time_heard; 876 877 /* When was the last time that we sent a chunk using this 878 * transport? We use this to check for idle transports 879 */ 880 unsigned long last_time_sent; 881 882 /* Last time(in jiffies) when cwnd is reduced due to the congestion 883 * indication based on ECNE chunk. 884 */ 885 unsigned long last_time_ecne_reduced; 886 887 __be16 encap_port; 888 889 /* This is the max_retrans value for the transport and will 890 * be initialized from the assocs value. This can be changed 891 * using the SCTP_SET_PEER_ADDR_PARAMS socket option. 892 */ 893 __u16 pathmaxrxt; 894 895 __u32 flowlabel; 896 __u8 dscp; 897 898 /* This is the partially failed retrans value for the transport 899 * and will be initialized from the assocs value. This can be changed 900 * using the SCTP_PEER_ADDR_THLDS socket option 901 */ 902 __u16 pf_retrans; 903 /* Used for primary path switchover. */ 904 __u16 ps_retrans; 905 /* PMTU : The current known path MTU. */ 906 __u32 pathmtu; 907 908 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 909 __u32 param_flags; 910 911 /* The number of times INIT has been sent on this transport. */ 912 int init_sent_count; 913 914 /* state : The current state of this destination, 915 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN. 916 */ 917 int state; 918 919 /* These are the error stats for this destination. */ 920 921 /* Error count : The current error count for this destination. */ 922 unsigned short error_count; 923 924 /* Per : A timer used by each destination. 925 * Destination : 926 * Timer : 927 * 928 * [Everywhere else in the text this is called T3-rtx. -ed] 929 */ 930 struct timer_list T3_rtx_timer; 931 932 /* Heartbeat timer is per destination. */ 933 struct timer_list hb_timer; 934 935 /* Timer to handle ICMP proto unreachable envets */ 936 struct timer_list proto_unreach_timer; 937 938 /* Timer to handler reconf chunk rtx */ 939 struct timer_list reconf_timer; 940 941 /* Timer to send a probe HB packet for PLPMTUD */ 942 struct timer_list probe_timer; 943 944 /* Since we're using per-destination retransmission timers 945 * (see above), we're also using per-destination "transmitted" 946 * queues. This probably ought to be a private struct 947 * accessible only within the outqueue, but it's not, yet. 948 */ 949 struct list_head transmitted; 950 951 /* We build bundle-able packets for this transport here. */ 952 struct sctp_packet packet; 953 954 /* This is the list of transports that have chunks to send. */ 955 struct list_head send_ready; 956 957 /* State information saved for SFR_CACC algorithm. The key 958 * idea in SFR_CACC is to maintain state at the sender on a 959 * per-destination basis when a changeover happens. 960 * char changeover_active; 961 * char cycling_changeover; 962 * __u32 next_tsn_at_change; 963 * char cacc_saw_newack; 964 */ 965 struct { 966 /* An unsigned integer, which stores the next TSN to be 967 * used by the sender, at the moment of changeover. 968 */ 969 __u32 next_tsn_at_change; 970 971 /* A flag which indicates the occurrence of a changeover */ 972 char changeover_active; 973 974 /* A flag which indicates whether the change of primary is 975 * the first switch to this destination address during an 976 * active switch. 977 */ 978 char cycling_changeover; 979 980 /* A temporary flag, which is used during the processing of 981 * a SACK to estimate the causative TSN(s)'s group. 982 */ 983 char cacc_saw_newack; 984 } cacc; 985 986 struct { 987 __u16 pmtu; 988 __u16 probe_size; 989 __u16 probe_high; 990 __u8 probe_count; 991 __u8 state; 992 } pl; /* plpmtud related */ 993 994 /* 64-bit random number sent with heartbeat. */ 995 __u64 hb_nonce; 996 997 struct rcu_head rcu; 998 }; 999 1000 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *, 1001 gfp_t); 1002 void sctp_transport_set_owner(struct sctp_transport *, 1003 struct sctp_association *); 1004 void sctp_transport_route(struct sctp_transport *, union sctp_addr *, 1005 struct sctp_sock *); 1006 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk); 1007 void sctp_transport_free(struct sctp_transport *); 1008 void sctp_transport_reset_t3_rtx(struct sctp_transport *); 1009 void sctp_transport_reset_hb_timer(struct sctp_transport *); 1010 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport); 1011 void sctp_transport_reset_probe_timer(struct sctp_transport *transport); 1012 int sctp_transport_hold(struct sctp_transport *); 1013 void sctp_transport_put(struct sctp_transport *); 1014 void sctp_transport_update_rto(struct sctp_transport *, __u32); 1015 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); 1016 void sctp_transport_lower_cwnd(struct sctp_transport *t, 1017 enum sctp_lower_cwnd reason); 1018 void sctp_transport_burst_limited(struct sctp_transport *); 1019 void sctp_transport_burst_reset(struct sctp_transport *); 1020 unsigned long sctp_transport_timeout(struct sctp_transport *); 1021 void sctp_transport_reset(struct sctp_transport *t); 1022 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu); 1023 void sctp_transport_immediate_rtx(struct sctp_transport *); 1024 void sctp_transport_dst_release(struct sctp_transport *t); 1025 void sctp_transport_dst_confirm(struct sctp_transport *t); 1026 void sctp_transport_pl_send(struct sctp_transport *t); 1027 1028 1029 /* This is the structure we use to queue packets as they come into 1030 * SCTP. We write packets to it and read chunks from it. 1031 */ 1032 struct sctp_inq { 1033 /* This is actually a queue of sctp_chunk each 1034 * containing a partially decoded packet. 1035 */ 1036 struct list_head in_chunk_list; 1037 /* This is the packet which is currently off the in queue and is 1038 * being worked on through the inbound chunk processing. 1039 */ 1040 struct sctp_chunk *in_progress; 1041 1042 /* This is the delayed task to finish delivering inbound 1043 * messages. 1044 */ 1045 struct work_struct immediate; 1046 }; 1047 1048 void sctp_inq_init(struct sctp_inq *); 1049 void sctp_inq_free(struct sctp_inq *); 1050 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); 1051 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); 1052 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *); 1053 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t); 1054 1055 /* This is the structure we use to hold outbound chunks. You push 1056 * chunks in and they automatically pop out the other end as bundled 1057 * packets (it calls (*output_handler)()). 1058 * 1059 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, 1060 * and 8.2 of the v13 draft. 1061 * 1062 * It handles retransmissions. The connection to the timeout portion 1063 * of the state machine is through sctp_..._timeout() and timeout_handler. 1064 * 1065 * If you feed it SACKs, it will eat them. 1066 * 1067 * If you give it big chunks, it will fragment them. 1068 * 1069 * It assigns TSN's to data chunks. This happens at the last possible 1070 * instant before transmission. 1071 * 1072 * When free()'d, it empties itself out via output_handler(). 1073 */ 1074 struct sctp_outq { 1075 struct sctp_association *asoc; 1076 1077 /* Data pending that has never been transmitted. */ 1078 struct list_head out_chunk_list; 1079 1080 /* Stream scheduler being used */ 1081 struct sctp_sched_ops *sched; 1082 1083 unsigned int out_qlen; /* Total length of queued data chunks. */ 1084 1085 /* Error of send failed, may used in SCTP_SEND_FAILED event. */ 1086 unsigned int error; 1087 1088 /* These are control chunks we want to send. */ 1089 struct list_head control_chunk_list; 1090 1091 /* These are chunks that have been sacked but are above the 1092 * CTSN, or cumulative tsn ack point. 1093 */ 1094 struct list_head sacked; 1095 1096 /* Put chunks on this list to schedule them for 1097 * retransmission. 1098 */ 1099 struct list_head retransmit; 1100 1101 /* Put chunks on this list to save them for FWD TSN processing as 1102 * they were abandoned. 1103 */ 1104 struct list_head abandoned; 1105 1106 /* How many unackd bytes do we have in-flight? */ 1107 __u32 outstanding_bytes; 1108 1109 /* Are we doing fast-rtx on this queue */ 1110 char fast_rtx; 1111 1112 /* Corked? */ 1113 char cork; 1114 }; 1115 1116 void sctp_outq_init(struct sctp_association *, struct sctp_outq *); 1117 void sctp_outq_teardown(struct sctp_outq *); 1118 void sctp_outq_free(struct sctp_outq*); 1119 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t); 1120 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *); 1121 int sctp_outq_is_empty(const struct sctp_outq *); 1122 void sctp_outq_restart(struct sctp_outq *); 1123 1124 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport, 1125 enum sctp_retransmit_reason reason); 1126 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); 1127 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp); 1128 void sctp_prsctp_prune(struct sctp_association *asoc, 1129 struct sctp_sndrcvinfo *sinfo, int msg_len); 1130 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn); 1131 /* Uncork and flush an outqueue. */ 1132 static inline void sctp_outq_cork(struct sctp_outq *q) 1133 { 1134 q->cork = 1; 1135 } 1136 1137 /* SCTP skb control block. 1138 * sctp_input_cb is currently used on rx and sock rx queue 1139 */ 1140 struct sctp_input_cb { 1141 union { 1142 struct inet_skb_parm h4; 1143 #if IS_ENABLED(CONFIG_IPV6) 1144 struct inet6_skb_parm h6; 1145 #endif 1146 } header; 1147 struct sctp_chunk *chunk; 1148 struct sctp_af *af; 1149 __be16 encap_port; 1150 }; 1151 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0])) 1152 1153 struct sctp_output_cb { 1154 struct sk_buff *last; 1155 }; 1156 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0])) 1157 1158 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb) 1159 { 1160 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; 1161 1162 return chunk->head_skb ? : skb; 1163 } 1164 1165 /* These bind address data fields common between endpoints and associations */ 1166 struct sctp_bind_addr { 1167 1168 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1169 * 1170 * SCTP Port: The local SCTP port number the endpoint is 1171 * bound to. 1172 */ 1173 __u16 port; 1174 1175 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1176 * 1177 * Address List: The list of IP addresses that this instance 1178 * has bound. This information is passed to one's 1179 * peer(s) in INIT and INIT ACK chunks. 1180 */ 1181 struct list_head address_list; 1182 }; 1183 1184 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); 1185 void sctp_bind_addr_free(struct sctp_bind_addr *); 1186 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest, 1187 const struct sctp_bind_addr *src, 1188 enum sctp_scope scope, gfp_t gfp, 1189 int flags); 1190 int sctp_bind_addr_dup(struct sctp_bind_addr *dest, 1191 const struct sctp_bind_addr *src, 1192 gfp_t gfp); 1193 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, 1194 int new_size, __u8 addr_state, gfp_t gfp); 1195 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); 1196 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, 1197 struct sctp_sock *); 1198 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *, 1199 struct sctp_sock *, struct sctp_sock *); 1200 int sctp_bind_addr_state(const struct sctp_bind_addr *bp, 1201 const union sctp_addr *addr); 1202 int sctp_bind_addrs_check(struct sctp_sock *sp, 1203 struct sctp_sock *sp2, int cnt2); 1204 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, 1205 const union sctp_addr *addrs, 1206 int addrcnt, 1207 struct sctp_sock *opt); 1208 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, 1209 int *addrs_len, 1210 gfp_t gfp); 1211 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, 1212 __u16 port, gfp_t gfp); 1213 1214 enum sctp_scope sctp_scope(const union sctp_addr *addr); 1215 int sctp_in_scope(struct net *net, const union sctp_addr *addr, 1216 const enum sctp_scope scope); 1217 int sctp_is_any(struct sock *sk, const union sctp_addr *addr); 1218 int sctp_is_ep_boundall(struct sock *sk); 1219 1220 1221 /* What type of endpoint? */ 1222 enum sctp_endpoint_type { 1223 SCTP_EP_TYPE_SOCKET, 1224 SCTP_EP_TYPE_ASSOCIATION, 1225 }; 1226 1227 /* 1228 * A common base class to bridge the implmentation view of a 1229 * socket (usually listening) endpoint versus an association's 1230 * local endpoint. 1231 * This common structure is useful for several purposes: 1232 * 1) Common interface for lookup routines. 1233 * a) Subfunctions work for either endpoint or association 1234 * b) Single interface to lookup allows hiding the lookup lock rather 1235 * than acquiring it externally. 1236 * 2) Common interface for the inbound chunk handling/state machine. 1237 * 3) Common object handling routines for reference counting, etc. 1238 * 4) Disentangle association lookup from endpoint lookup, where we 1239 * do not have to find our endpoint to find our association. 1240 * 1241 */ 1242 1243 struct sctp_ep_common { 1244 /* Fields to help us manage our entries in the hash tables. */ 1245 struct hlist_node node; 1246 int hashent; 1247 1248 /* Runtime type information. What kind of endpoint is this? */ 1249 enum sctp_endpoint_type type; 1250 1251 /* Some fields to help us manage this object. 1252 * refcnt - Reference count access to this object. 1253 * dead - Do not attempt to use this object. 1254 */ 1255 refcount_t refcnt; 1256 bool dead; 1257 1258 /* What socket does this endpoint belong to? */ 1259 struct sock *sk; 1260 1261 /* Cache netns and it won't change once set */ 1262 struct net *net; 1263 1264 /* This is where we receive inbound chunks. */ 1265 struct sctp_inq inqueue; 1266 1267 /* This substructure includes the defining parameters of the 1268 * endpoint: 1269 * bind_addr.port is our shared port number. 1270 * bind_addr.address_list is our set of local IP addresses. 1271 */ 1272 struct sctp_bind_addr bind_addr; 1273 }; 1274 1275 1276 /* RFC Section 1.4 Key Terms 1277 * 1278 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a 1279 * multi-homed host, an SCTP endpoint is represented to its peers as a 1280 * combination of a set of eligible destination transport addresses to 1281 * which SCTP packets can be sent and a set of eligible source 1282 * transport addresses from which SCTP packets can be received. 1283 * All transport addresses used by an SCTP endpoint must use the 1284 * same port number, but can use multiple IP addresses. A transport 1285 * address used by an SCTP endpoint must not be used by another 1286 * SCTP endpoint. In other words, a transport address is unique 1287 * to an SCTP endpoint. 1288 * 1289 * From an implementation perspective, each socket has one of these. 1290 * A TCP-style socket will have exactly one association on one of 1291 * these. An UDP-style socket will have multiple associations hanging 1292 * off one of these. 1293 */ 1294 1295 struct sctp_endpoint { 1296 /* Common substructure for endpoint and association. */ 1297 struct sctp_ep_common base; 1298 1299 /* Associations: A list of current associations and mappings 1300 * to the data consumers for each association. This 1301 * may be in the form of a hash table or other 1302 * implementation dependent structure. The data 1303 * consumers may be process identification 1304 * information such as file descriptors, named pipe 1305 * pointer, or table pointers dependent on how SCTP 1306 * is implemented. 1307 */ 1308 /* This is really a list of struct sctp_association entries. */ 1309 struct list_head asocs; 1310 1311 /* Secret Key: A secret key used by this endpoint to compute 1312 * the MAC. This SHOULD be a cryptographic quality 1313 * random number with a sufficient length. 1314 * Discussion in [RFC1750] can be helpful in 1315 * selection of the key. 1316 */ 1317 __u8 secret_key[SCTP_SECRET_SIZE]; 1318 1319 /* digest: This is a digest of the sctp cookie. This field is 1320 * only used on the receive path when we try to validate 1321 * that the cookie has not been tampered with. We put 1322 * this here so we pre-allocate this once and can re-use 1323 * on every receive. 1324 */ 1325 __u8 *digest; 1326 1327 /* sendbuf acct. policy. */ 1328 __u32 sndbuf_policy; 1329 1330 /* rcvbuf acct. policy. */ 1331 __u32 rcvbuf_policy; 1332 1333 /* SCTP AUTH: array of the HMACs that will be allocated 1334 * we need this per association so that we don't serialize 1335 */ 1336 struct crypto_shash **auth_hmacs; 1337 1338 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */ 1339 struct sctp_hmac_algo_param *auth_hmacs_list; 1340 1341 /* SCTP-AUTH: chunks to authenticate encoded into parameter */ 1342 struct sctp_chunks_param *auth_chunk_list; 1343 1344 /* SCTP-AUTH: endpoint shared keys */ 1345 struct list_head endpoint_shared_keys; 1346 __u16 active_key_id; 1347 __u8 ecn_enable:1, 1348 auth_enable:1, 1349 intl_enable:1, 1350 prsctp_enable:1, 1351 asconf_enable:1, 1352 reconf_enable:1; 1353 1354 __u8 strreset_enable; 1355 1356 /* Security identifiers from incoming (INIT). These are set by 1357 * security_sctp_assoc_request(). These will only be used by 1358 * SCTP TCP type sockets and peeled off connections as they 1359 * cause a new socket to be generated. security_sctp_sk_clone() 1360 * will then plug these into the new socket. 1361 */ 1362 1363 u32 secid; 1364 u32 peer_secid; 1365 }; 1366 1367 /* Recover the outter endpoint structure. */ 1368 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) 1369 { 1370 struct sctp_endpoint *ep; 1371 1372 ep = container_of(base, struct sctp_endpoint, base); 1373 return ep; 1374 } 1375 1376 /* These are function signatures for manipulating endpoints. */ 1377 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t); 1378 void sctp_endpoint_free(struct sctp_endpoint *); 1379 void sctp_endpoint_put(struct sctp_endpoint *); 1380 void sctp_endpoint_hold(struct sctp_endpoint *); 1381 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); 1382 struct sctp_association *sctp_endpoint_lookup_assoc( 1383 const struct sctp_endpoint *ep, 1384 const union sctp_addr *paddr, 1385 struct sctp_transport **); 1386 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep, 1387 const union sctp_addr *paddr); 1388 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *, 1389 struct net *, const union sctp_addr *); 1390 bool sctp_has_association(struct net *net, const union sctp_addr *laddr, 1391 const union sctp_addr *paddr); 1392 1393 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep, 1394 const struct sctp_association *asoc, 1395 enum sctp_cid cid, struct sctp_init_chunk *peer_init, 1396 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk); 1397 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk, 1398 const union sctp_addr *peer, 1399 struct sctp_init_chunk *init, gfp_t gfp); 1400 __u32 sctp_generate_tag(const struct sctp_endpoint *); 1401 __u32 sctp_generate_tsn(const struct sctp_endpoint *); 1402 1403 struct sctp_inithdr_host { 1404 __u32 init_tag; 1405 __u32 a_rwnd; 1406 __u16 num_outbound_streams; 1407 __u16 num_inbound_streams; 1408 __u32 initial_tsn; 1409 }; 1410 1411 struct sctp_stream_priorities { 1412 /* List of priorities scheduled */ 1413 struct list_head prio_sched; 1414 /* List of streams scheduled */ 1415 struct list_head active; 1416 /* The next stream in line */ 1417 struct sctp_stream_out_ext *next; 1418 __u16 prio; 1419 }; 1420 1421 struct sctp_stream_out_ext { 1422 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 1423 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 1424 struct list_head outq; /* chunks enqueued by this stream */ 1425 union { 1426 struct { 1427 /* Scheduled streams list */ 1428 struct list_head prio_list; 1429 struct sctp_stream_priorities *prio_head; 1430 }; 1431 /* Fields used by RR scheduler */ 1432 struct { 1433 struct list_head rr_list; 1434 }; 1435 }; 1436 }; 1437 1438 struct sctp_stream_out { 1439 union { 1440 __u32 mid; 1441 __u16 ssn; 1442 }; 1443 __u32 mid_uo; 1444 struct sctp_stream_out_ext *ext; 1445 __u8 state; 1446 }; 1447 1448 struct sctp_stream_in { 1449 union { 1450 __u32 mid; 1451 __u16 ssn; 1452 }; 1453 __u32 mid_uo; 1454 __u32 fsn; 1455 __u32 fsn_uo; 1456 char pd_mode; 1457 char pd_mode_uo; 1458 }; 1459 1460 struct sctp_stream { 1461 GENRADIX(struct sctp_stream_out) out; 1462 GENRADIX(struct sctp_stream_in) in; 1463 1464 __u16 outcnt; 1465 __u16 incnt; 1466 /* Current stream being sent, if any */ 1467 struct sctp_stream_out *out_curr; 1468 union { 1469 /* Fields used by priority scheduler */ 1470 struct { 1471 /* List of priorities scheduled */ 1472 struct list_head prio_list; 1473 }; 1474 /* Fields used by RR scheduler */ 1475 struct { 1476 /* List of streams scheduled */ 1477 struct list_head rr_list; 1478 /* The next stream in line */ 1479 struct sctp_stream_out_ext *rr_next; 1480 }; 1481 }; 1482 struct sctp_stream_interleave *si; 1483 }; 1484 1485 static inline struct sctp_stream_out *sctp_stream_out( 1486 struct sctp_stream *stream, 1487 __u16 sid) 1488 { 1489 return genradix_ptr(&stream->out, sid); 1490 } 1491 1492 static inline struct sctp_stream_in *sctp_stream_in( 1493 struct sctp_stream *stream, 1494 __u16 sid) 1495 { 1496 return genradix_ptr(&stream->in, sid); 1497 } 1498 1499 #define SCTP_SO(s, i) sctp_stream_out((s), (i)) 1500 #define SCTP_SI(s, i) sctp_stream_in((s), (i)) 1501 1502 #define SCTP_STREAM_CLOSED 0x00 1503 #define SCTP_STREAM_OPEN 0x01 1504 1505 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream) 1506 { 1507 return stream->si->data_chunk_len; 1508 } 1509 1510 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream) 1511 { 1512 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr); 1513 } 1514 1515 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream) 1516 { 1517 return stream->si->ftsn_chunk_len; 1518 } 1519 1520 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream) 1521 { 1522 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr); 1523 } 1524 1525 /* SCTP_GET_ASSOC_STATS counters */ 1526 struct sctp_priv_assoc_stats { 1527 /* Maximum observed rto in the association during subsequent 1528 * observations. Value is set to 0 if no RTO measurement took place 1529 * The transport where the max_rto was observed is returned in 1530 * obs_rto_ipaddr 1531 */ 1532 struct sockaddr_storage obs_rto_ipaddr; 1533 __u64 max_obs_rto; 1534 /* Total In and Out SACKs received and sent */ 1535 __u64 isacks; 1536 __u64 osacks; 1537 /* Total In and Out packets received and sent */ 1538 __u64 opackets; 1539 __u64 ipackets; 1540 /* Total retransmitted chunks */ 1541 __u64 rtxchunks; 1542 /* TSN received > next expected */ 1543 __u64 outofseqtsns; 1544 /* Duplicate Chunks received */ 1545 __u64 idupchunks; 1546 /* Gap Ack Blocks received */ 1547 __u64 gapcnt; 1548 /* Unordered data chunks sent and received */ 1549 __u64 ouodchunks; 1550 __u64 iuodchunks; 1551 /* Ordered data chunks sent and received */ 1552 __u64 oodchunks; 1553 __u64 iodchunks; 1554 /* Control chunks sent and received */ 1555 __u64 octrlchunks; 1556 __u64 ictrlchunks; 1557 }; 1558 1559 /* RFC2960 1560 * 1561 * 12. Recommended Transmission Control Block (TCB) Parameters 1562 * 1563 * This section details a recommended set of parameters that should 1564 * be contained within the TCB for an implementation. This section is 1565 * for illustrative purposes and should not be deemed as requirements 1566 * on an implementation or as an exhaustive list of all parameters 1567 * inside an SCTP TCB. Each implementation may need its own additional 1568 * parameters for optimization. 1569 */ 1570 1571 1572 /* Here we have information about each individual association. */ 1573 struct sctp_association { 1574 1575 /* A base structure common to endpoint and association. 1576 * In this context, it represents the associations's view 1577 * of the local endpoint of the association. 1578 */ 1579 struct sctp_ep_common base; 1580 1581 /* Associations on the same socket. */ 1582 struct list_head asocs; 1583 1584 /* association id. */ 1585 sctp_assoc_t assoc_id; 1586 1587 /* This is our parent endpoint. */ 1588 struct sctp_endpoint *ep; 1589 1590 /* These are those association elements needed in the cookie. */ 1591 struct sctp_cookie c; 1592 1593 /* This is all information about our peer. */ 1594 struct { 1595 /* transport_addr_list 1596 * 1597 * Peer : A list of SCTP transport addresses that the 1598 * Transport : peer is bound to. This information is derived 1599 * Address : from the INIT or INIT ACK and is used to 1600 * List : associate an inbound packet with a given 1601 * : association. Normally this information is 1602 * : hashed or keyed for quick lookup and access 1603 * : of the TCB. 1604 * : The list is also initialized with the list 1605 * : of addresses passed with the sctp_connectx() 1606 * : call. 1607 * 1608 * It is a list of SCTP_transport's. 1609 */ 1610 struct list_head transport_addr_list; 1611 1612 /* rwnd 1613 * 1614 * Peer Rwnd : Current calculated value of the peer's rwnd. 1615 */ 1616 __u32 rwnd; 1617 1618 /* transport_count 1619 * 1620 * Peer : A count of the number of peer addresses 1621 * Transport : in the Peer Transport Address List. 1622 * Address : 1623 * Count : 1624 */ 1625 __u16 transport_count; 1626 1627 /* port 1628 * The transport layer port number. 1629 */ 1630 __u16 port; 1631 1632 /* primary_path 1633 * 1634 * Primary : This is the current primary destination 1635 * Path : transport address of the peer endpoint. It 1636 * : may also specify a source transport address 1637 * : on this endpoint. 1638 * 1639 * All of these paths live on transport_addr_list. 1640 * 1641 * At the bakeoffs, we discovered that the intent of 1642 * primaryPath is that it only changes when the ULP 1643 * asks to have it changed. We add the activePath to 1644 * designate the connection we are currently using to 1645 * transmit new data and most control chunks. 1646 */ 1647 struct sctp_transport *primary_path; 1648 1649 /* Cache the primary path address here, when we 1650 * need a an address for msg_name. 1651 */ 1652 union sctp_addr primary_addr; 1653 1654 /* active_path 1655 * The path that we are currently using to 1656 * transmit new data and most control chunks. 1657 */ 1658 struct sctp_transport *active_path; 1659 1660 /* retran_path 1661 * 1662 * RFC2960 6.4 Multi-homed SCTP Endpoints 1663 * ... 1664 * Furthermore, when its peer is multi-homed, an 1665 * endpoint SHOULD try to retransmit a chunk to an 1666 * active destination transport address that is 1667 * different from the last destination address to 1668 * which the DATA chunk was sent. 1669 */ 1670 struct sctp_transport *retran_path; 1671 1672 /* Pointer to last transport I have sent on. */ 1673 struct sctp_transport *last_sent_to; 1674 1675 /* This is the last transport I have received DATA on. */ 1676 struct sctp_transport *last_data_from; 1677 1678 /* 1679 * Mapping An array of bits or bytes indicating which out of 1680 * Array order TSN's have been received (relative to the 1681 * Last Rcvd TSN). If no gaps exist, i.e. no out of 1682 * order packets have been received, this array 1683 * will be set to all zero. This structure may be 1684 * in the form of a circular buffer or bit array. 1685 * 1686 * Last Rcvd : This is the last TSN received in 1687 * TSN : sequence. This value is set initially by 1688 * : taking the peer's Initial TSN, received in 1689 * : the INIT or INIT ACK chunk, and subtracting 1690 * : one from it. 1691 * 1692 * Throughout most of the specification this is called the 1693 * "Cumulative TSN ACK Point". In this case, we 1694 * ignore the advice in 12.2 in favour of the term 1695 * used in the bulk of the text. This value is hidden 1696 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn(). 1697 */ 1698 struct sctp_tsnmap tsn_map; 1699 1700 /* This mask is used to disable sending the ASCONF chunk 1701 * with specified parameter to peer. 1702 */ 1703 __be16 addip_disabled_mask; 1704 1705 /* These are capabilities which our peer advertised. */ 1706 __u16 ecn_capable:1, /* Can peer do ECN? */ 1707 ipv4_address:1, /* Peer understands IPv4 addresses? */ 1708 ipv6_address:1, /* Peer understands IPv6 addresses? */ 1709 hostname_address:1, /* Peer understands DNS addresses? */ 1710 asconf_capable:1, /* Does peer support ADDIP? */ 1711 prsctp_capable:1, /* Can peer do PR-SCTP? */ 1712 reconf_capable:1, /* Can peer do RE-CONFIG? */ 1713 intl_capable:1, /* Can peer do INTERLEAVE */ 1714 auth_capable:1, /* Is peer doing SCTP-AUTH? */ 1715 /* sack_needed: 1716 * This flag indicates if the next received 1717 * packet is to be responded to with a 1718 * SACK. This is initialized to 0. When a packet 1719 * is received sack_cnt is incremented. If this value 1720 * reaches 2 or more, a SACK is sent and the 1721 * value is reset to 0. Note: This is used only 1722 * when no DATA chunks are received out of 1723 * order. When DATA chunks are out of order, 1724 * SACK's are not delayed (see Section 6). 1725 */ 1726 sack_needed:1, /* Do we need to sack the peer? */ 1727 sack_generation:1, 1728 zero_window_announced:1; 1729 1730 __u32 sack_cnt; 1731 1732 __u32 adaptation_ind; /* Adaptation Code point. */ 1733 1734 struct sctp_inithdr_host i; 1735 void *cookie; 1736 int cookie_len; 1737 1738 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. 1739 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the 1740 * Initial TSN Value minus 1 1741 */ 1742 __u32 addip_serial; 1743 1744 /* SCTP-AUTH: We need to know pears random number, hmac list 1745 * and authenticated chunk list. All that is part of the 1746 * cookie and these are just pointers to those locations 1747 */ 1748 struct sctp_random_param *peer_random; 1749 struct sctp_chunks_param *peer_chunks; 1750 struct sctp_hmac_algo_param *peer_hmacs; 1751 } peer; 1752 1753 /* State : A state variable indicating what state the 1754 * : association is in, i.e. COOKIE-WAIT, 1755 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, 1756 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. 1757 * 1758 * Note: No "CLOSED" state is illustrated since if a 1759 * association is "CLOSED" its TCB SHOULD be removed. 1760 * 1761 * In this implementation we DO have a CLOSED 1762 * state which is used during initiation and shutdown. 1763 * 1764 * State takes values from SCTP_STATE_*. 1765 */ 1766 enum sctp_state state; 1767 1768 /* Overall : The overall association error count. 1769 * Error Count : [Clear this any time I get something.] 1770 */ 1771 int overall_error_count; 1772 1773 /* The cookie life I award for any cookie. */ 1774 ktime_t cookie_life; 1775 1776 /* These are the association's initial, max, and min RTO values. 1777 * These values will be initialized by system defaults, but can 1778 * be modified via the SCTP_RTOINFO socket option. 1779 */ 1780 unsigned long rto_initial; 1781 unsigned long rto_max; 1782 unsigned long rto_min; 1783 1784 /* Maximum number of new data packets that can be sent in a burst. */ 1785 int max_burst; 1786 1787 /* This is the max_retrans value for the association. This value will 1788 * be initialized from system defaults, but can be 1789 * modified by the SCTP_ASSOCINFO socket option. 1790 */ 1791 int max_retrans; 1792 1793 /* This is the partially failed retrans value for the transport 1794 * and will be initialized from the assocs value. This can be 1795 * changed using the SCTP_PEER_ADDR_THLDS socket option 1796 */ 1797 __u16 pf_retrans; 1798 /* Used for primary path switchover. */ 1799 __u16 ps_retrans; 1800 1801 /* Maximum number of times the endpoint will retransmit INIT */ 1802 __u16 max_init_attempts; 1803 1804 /* How many times have we resent an INIT? */ 1805 __u16 init_retries; 1806 1807 /* The largest timeout or RTO value to use in attempting an INIT */ 1808 unsigned long max_init_timeo; 1809 1810 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 1811 * the destination address every heartbeat interval. This value 1812 * will be inherited by all new transports. 1813 */ 1814 unsigned long hbinterval; 1815 unsigned long probe_interval; 1816 1817 __be16 encap_port; 1818 1819 /* This is the max_retrans value for new transports in the 1820 * association. 1821 */ 1822 __u16 pathmaxrxt; 1823 1824 __u32 flowlabel; 1825 __u8 dscp; 1826 1827 /* Flag that path mtu update is pending */ 1828 __u8 pmtu_pending; 1829 1830 /* Association : The smallest PMTU discovered for all of the 1831 * PMTU : peer's transport addresses. 1832 */ 1833 __u32 pathmtu; 1834 1835 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1836 __u32 param_flags; 1837 1838 __u32 sackfreq; 1839 /* SACK delay timeout */ 1840 unsigned long sackdelay; 1841 1842 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES]; 1843 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; 1844 1845 /* Transport to which SHUTDOWN chunk was last sent. */ 1846 struct sctp_transport *shutdown_last_sent_to; 1847 1848 /* Transport to which INIT chunk was last sent. */ 1849 struct sctp_transport *init_last_sent_to; 1850 1851 /* How many times have we resent a SHUTDOWN */ 1852 int shutdown_retries; 1853 1854 /* Next TSN : The next TSN number to be assigned to a new 1855 * : DATA chunk. This is sent in the INIT or INIT 1856 * : ACK chunk to the peer and incremented each 1857 * : time a DATA chunk is assigned a TSN 1858 * : (normally just prior to transmit or during 1859 * : fragmentation). 1860 */ 1861 __u32 next_tsn; 1862 1863 /* 1864 * Last Rcvd : This is the last TSN received in sequence. This value 1865 * TSN : is set initially by taking the peer's Initial TSN, 1866 * : received in the INIT or INIT ACK chunk, and 1867 * : subtracting one from it. 1868 * 1869 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. 1870 */ 1871 1872 __u32 ctsn_ack_point; 1873 1874 /* PR-SCTP Advanced.Peer.Ack.Point */ 1875 __u32 adv_peer_ack_point; 1876 1877 /* Highest TSN that is acknowledged by incoming SACKs. */ 1878 __u32 highest_sacked; 1879 1880 /* TSN marking the fast recovery exit point */ 1881 __u32 fast_recovery_exit; 1882 1883 /* Flag to track the current fast recovery state */ 1884 __u8 fast_recovery; 1885 1886 /* The number of unacknowledged data chunks. Reported through 1887 * the SCTP_STATUS sockopt. 1888 */ 1889 __u16 unack_data; 1890 1891 /* The total number of data chunks that we've had to retransmit 1892 * as the result of a T3 timer expiration 1893 */ 1894 __u32 rtx_data_chunks; 1895 1896 /* This is the association's receive buffer space. This value is used 1897 * to set a_rwnd field in an INIT or a SACK chunk. 1898 */ 1899 __u32 rwnd; 1900 1901 /* This is the last advertised value of rwnd over a SACK chunk. */ 1902 __u32 a_rwnd; 1903 1904 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed 1905 * to slop over a maximum of the association's frag_point. 1906 */ 1907 __u32 rwnd_over; 1908 1909 /* Keeps treack of rwnd pressure. This happens when we have 1910 * a window, but not recevie buffer (i.e small packets). This one 1911 * is releases slowly (1 PMTU at a time ). 1912 */ 1913 __u32 rwnd_press; 1914 1915 /* This is the sndbuf size in use for the association. 1916 * This corresponds to the sndbuf size for the association, 1917 * as specified in the sk->sndbuf. 1918 */ 1919 int sndbuf_used; 1920 1921 /* This is the amount of memory that this association has allocated 1922 * in the receive path at any given time. 1923 */ 1924 atomic_t rmem_alloc; 1925 1926 /* This is the wait queue head for send requests waiting on 1927 * the association sndbuf space. 1928 */ 1929 wait_queue_head_t wait; 1930 1931 /* The message size at which SCTP fragmentation will occur. */ 1932 __u32 frag_point; 1933 __u32 user_frag; 1934 1935 /* Counter used to count INIT errors. */ 1936 int init_err_counter; 1937 1938 /* Count the number of INIT cycles (for doubling timeout). */ 1939 int init_cycle; 1940 1941 /* Default send parameters. */ 1942 __u16 default_stream; 1943 __u16 default_flags; 1944 __u32 default_ppid; 1945 __u32 default_context; 1946 __u32 default_timetolive; 1947 1948 /* Default receive parameters */ 1949 __u32 default_rcv_context; 1950 1951 /* Stream arrays */ 1952 struct sctp_stream stream; 1953 1954 /* All outbound chunks go through this structure. */ 1955 struct sctp_outq outqueue; 1956 1957 /* A smart pipe that will handle reordering and fragmentation, 1958 * as well as handle passing events up to the ULP. 1959 */ 1960 struct sctp_ulpq ulpq; 1961 1962 /* Last TSN that caused an ECNE Chunk to be sent. */ 1963 __u32 last_ecne_tsn; 1964 1965 /* Last TSN that caused a CWR Chunk to be sent. */ 1966 __u32 last_cwr_tsn; 1967 1968 /* How many duplicated TSNs have we seen? */ 1969 int numduptsns; 1970 1971 /* These are to support 1972 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses 1973 * and Enforcement of Flow and Message Limits" 1974 * <draft-ietf-tsvwg-addip-sctp-02.txt> 1975 * or "ADDIP" for short. 1976 */ 1977 1978 1979 1980 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1981 * 1982 * R1) One and only one ASCONF Chunk MAY be in transit and 1983 * unacknowledged at any one time. If a sender, after sending 1984 * an ASCONF chunk, decides it needs to transfer another 1985 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1986 * returns from the previous ASCONF Chunk before sending a 1987 * subsequent ASCONF. Note this restriction binds each side, 1988 * so at any time two ASCONF may be in-transit on any given 1989 * association (one sent from each endpoint). 1990 * 1991 * [This is our one-and-only-one ASCONF in flight. If we do 1992 * not have an ASCONF in flight, this is NULL.] 1993 */ 1994 struct sctp_chunk *addip_last_asconf; 1995 1996 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk. 1997 * 1998 * This is needed to implement itmes E1 - E4 of the updated 1999 * spec. Here is the justification: 2000 * 2001 * Since the peer may bundle multiple ASCONF chunks toward us, 2002 * we now need the ability to cache multiple ACKs. The section 2003 * describes in detail how they are cached and cleaned up. 2004 */ 2005 struct list_head asconf_ack_list; 2006 2007 /* These ASCONF chunks are waiting to be sent. 2008 * 2009 * These chunaks can't be pushed to outqueue until receiving 2010 * ASCONF_ACK for the previous ASCONF indicated by 2011 * addip_last_asconf, so as to guarantee that only one ASCONF 2012 * is in flight at any time. 2013 * 2014 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 2015 * 2016 * In defining the ASCONF Chunk transfer procedures, it is 2017 * essential that these transfers MUST NOT cause congestion 2018 * within the network. To achieve this, we place these 2019 * restrictions on the transfer of ASCONF Chunks: 2020 * 2021 * R1) One and only one ASCONF Chunk MAY be in transit and 2022 * unacknowledged at any one time. If a sender, after sending 2023 * an ASCONF chunk, decides it needs to transfer another 2024 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 2025 * returns from the previous ASCONF Chunk before sending a 2026 * subsequent ASCONF. Note this restriction binds each side, 2027 * so at any time two ASCONF may be in-transit on any given 2028 * association (one sent from each endpoint). 2029 * 2030 * 2031 * [I really think this is EXACTLY the sort of intelligence 2032 * which already resides in sctp_outq. Please move this 2033 * queue and its supporting logic down there. --piggy] 2034 */ 2035 struct list_head addip_chunk_list; 2036 2037 /* ADDIP Section 4.1 ASCONF Chunk Procedures 2038 * 2039 * A2) A serial number should be assigned to the Chunk. The 2040 * serial number SHOULD be a monotonically increasing 2041 * number. The serial number SHOULD be initialized at 2042 * the start of the association to the same value as the 2043 * Initial TSN and every time a new ASCONF chunk is created 2044 * it is incremented by one after assigning the serial number 2045 * to the newly created chunk. 2046 * 2047 * ADDIP 2048 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) 2049 * 2050 * Serial Number : 32 bits (unsigned integer) 2051 * 2052 * This value represents a Serial Number for the ASCONF 2053 * Chunk. The valid range of Serial Number is from 0 to 2054 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 2055 * after reaching 4294967295. 2056 */ 2057 __u32 addip_serial; 2058 int src_out_of_asoc_ok; 2059 union sctp_addr *asconf_addr_del_pending; 2060 struct sctp_transport *new_transport; 2061 2062 /* SCTP AUTH: list of the endpoint shared keys. These 2063 * keys are provided out of band by the user applicaton 2064 * and can't change during the lifetime of the association 2065 */ 2066 struct list_head endpoint_shared_keys; 2067 2068 /* SCTP AUTH: 2069 * The current generated assocaition shared key (secret) 2070 */ 2071 struct sctp_auth_bytes *asoc_shared_key; 2072 struct sctp_shared_key *shkey; 2073 2074 /* SCTP AUTH: hmac id of the first peer requested algorithm 2075 * that we support. 2076 */ 2077 __u16 default_hmac_id; 2078 2079 __u16 active_key_id; 2080 2081 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */ 2082 temp:1, /* Is it a temporary association? */ 2083 pf_expose:2, /* Expose pf state? */ 2084 force_delay:1; 2085 2086 __u8 strreset_enable; 2087 __u8 strreset_outstanding; /* request param count on the fly */ 2088 2089 __u32 strreset_outseq; /* Update after receiving response */ 2090 __u32 strreset_inseq; /* Update after receiving request */ 2091 __u32 strreset_result[2]; /* save the results of last 2 responses */ 2092 2093 struct sctp_chunk *strreset_chunk; /* save request chunk */ 2094 2095 struct sctp_priv_assoc_stats stats; 2096 2097 int sent_cnt_removable; 2098 2099 __u16 subscribe; 2100 2101 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 2102 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 2103 2104 struct rcu_head rcu; 2105 }; 2106 2107 2108 /* An eyecatcher for determining if we are really looking at an 2109 * association data structure. 2110 */ 2111 enum { 2112 SCTP_ASSOC_EYECATCHER = 0xa550c123, 2113 }; 2114 2115 /* Recover the outter association structure. */ 2116 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) 2117 { 2118 struct sctp_association *asoc; 2119 2120 asoc = container_of(base, struct sctp_association, base); 2121 return asoc; 2122 } 2123 2124 /* These are function signatures for manipulating associations. */ 2125 2126 2127 struct sctp_association * 2128 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk, 2129 enum sctp_scope scope, gfp_t gfp); 2130 void sctp_association_free(struct sctp_association *); 2131 void sctp_association_put(struct sctp_association *); 2132 void sctp_association_hold(struct sctp_association *); 2133 2134 struct sctp_transport *sctp_assoc_choose_alter_transport( 2135 struct sctp_association *, struct sctp_transport *); 2136 void sctp_assoc_update_retran_path(struct sctp_association *); 2137 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, 2138 const union sctp_addr *); 2139 int sctp_assoc_lookup_laddr(struct sctp_association *asoc, 2140 const union sctp_addr *laddr); 2141 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, 2142 const union sctp_addr *address, 2143 const gfp_t gfp, 2144 const int peer_state); 2145 void sctp_assoc_del_peer(struct sctp_association *asoc, 2146 const union sctp_addr *addr); 2147 void sctp_assoc_rm_peer(struct sctp_association *asoc, 2148 struct sctp_transport *peer); 2149 void sctp_assoc_control_transport(struct sctp_association *asoc, 2150 struct sctp_transport *transport, 2151 enum sctp_transport_cmd command, 2152 sctp_sn_error_t error); 2153 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); 2154 void sctp_assoc_migrate(struct sctp_association *, struct sock *); 2155 int sctp_assoc_update(struct sctp_association *old, 2156 struct sctp_association *new); 2157 2158 __u32 sctp_association_get_next_tsn(struct sctp_association *); 2159 2160 void sctp_assoc_update_frag_point(struct sctp_association *asoc); 2161 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu); 2162 void sctp_assoc_sync_pmtu(struct sctp_association *asoc); 2163 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int); 2164 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int); 2165 void sctp_assoc_set_primary(struct sctp_association *, 2166 struct sctp_transport *); 2167 void sctp_assoc_del_nonprimary_peers(struct sctp_association *, 2168 struct sctp_transport *); 2169 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, 2170 enum sctp_scope scope, gfp_t gfp); 2171 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, 2172 struct sctp_cookie*, 2173 gfp_t gfp); 2174 int sctp_assoc_set_id(struct sctp_association *, gfp_t); 2175 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc); 2176 struct sctp_chunk *sctp_assoc_lookup_asconf_ack( 2177 const struct sctp_association *asoc, 2178 __be32 serial); 2179 void sctp_asconf_queue_teardown(struct sctp_association *asoc); 2180 2181 int sctp_cmp_addr_exact(const union sctp_addr *ss1, 2182 const union sctp_addr *ss2); 2183 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); 2184 2185 /* A convenience structure to parse out SCTP specific CMSGs. */ 2186 struct sctp_cmsgs { 2187 struct sctp_initmsg *init; 2188 struct sctp_sndrcvinfo *srinfo; 2189 struct sctp_sndinfo *sinfo; 2190 struct sctp_prinfo *prinfo; 2191 struct sctp_authinfo *authinfo; 2192 struct msghdr *addrs_msg; 2193 }; 2194 2195 /* Structure for tracking memory objects */ 2196 struct sctp_dbg_objcnt_entry { 2197 char *label; 2198 atomic_t *counter; 2199 }; 2200 2201 #endif /* __sctp_structs_h__ */ 2202