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