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