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