sctp_header.h revision 228031
1/*- 2 * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved. 3 * Copyright (c) 2008-2011, by Randall Stewart. All rights reserved. 4 * Copyright (c) 2008-2011, by Michael Tuexen. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are met: 8 * 9 * a) Redistributions of source code must retain the above copyright notice, 10 * this list of conditions and the following disclaimer. 11 * 12 * b) Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in 14 * the documentation and/or other materials provided with the distribution. 15 * 16 * c) Neither the name of Cisco Systems, Inc. nor the names of its 17 * contributors may be used to endorse or promote products derived 18 * from this software without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 22 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 24 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 30 * THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33/* $KAME: sctp_header.h,v 1.14 2005/03/06 16:04:17 itojun Exp $ */ 34 35#include <sys/cdefs.h> 36__FBSDID("$FreeBSD: head/sys/netinet/sctp_header.h 228031 2011-11-27 17:51:13Z tuexen $"); 37 38#ifndef __sctp_header_h__ 39#define __sctp_header_h__ 40 41#include <sys/time.h> 42#include <netinet/sctp.h> 43#include <netinet/sctp_constants.h> 44 45#define SCTP_PACKED __attribute__((packed)) 46 47/* 48 * Parameter structures 49 */ 50struct sctp_ipv4addr_param { 51 struct sctp_paramhdr ph;/* type=SCTP_IPV4_PARAM_TYPE, len=8 */ 52 uint32_t addr; /* IPV4 address */ 53} SCTP_PACKED; 54 55#define SCTP_V6_ADDR_BYTES 16 56 57 58struct sctp_ipv6addr_param { 59 struct sctp_paramhdr ph;/* type=SCTP_IPV6_PARAM_TYPE, len=20 */ 60 uint8_t addr[SCTP_V6_ADDR_BYTES]; /* IPV6 address */ 61} SCTP_PACKED; 62 63/* Cookie Preservative */ 64struct sctp_cookie_perserve_param { 65 struct sctp_paramhdr ph;/* type=SCTP_COOKIE_PRESERVE, len=8 */ 66 uint32_t time; /* time in ms to extend cookie */ 67} SCTP_PACKED; 68 69#define SCTP_ARRAY_MIN_LEN 1 70/* Host Name Address */ 71struct sctp_host_name_param { 72 struct sctp_paramhdr ph;/* type=SCTP_HOSTNAME_ADDRESS */ 73 char name[SCTP_ARRAY_MIN_LEN]; /* host name */ 74} SCTP_PACKED; 75 76/* 77 * This is the maximum padded size of a s-a-p 78 * so paramheadr + 3 address types (6 bytes) + 2 byte pad = 12 79 */ 80#define SCTP_MAX_ADDR_PARAMS_SIZE 12 81/* supported address type */ 82struct sctp_supported_addr_param { 83 struct sctp_paramhdr ph;/* type=SCTP_SUPPORTED_ADDRTYPE */ 84 uint16_t addr_type[2]; /* array of supported address types */ 85} SCTP_PACKED; 86 87/* ECN parameter */ 88struct sctp_ecn_supported_param { 89 struct sctp_paramhdr ph;/* type=SCTP_ECN_CAPABLE */ 90} SCTP_PACKED; 91 92 93/* heartbeat info parameter */ 94struct sctp_heartbeat_info_param { 95 struct sctp_paramhdr ph; 96 uint32_t time_value_1; 97 uint32_t time_value_2; 98 uint32_t random_value1; 99 uint32_t random_value2; 100 uint8_t addr_family; 101 uint8_t addr_len; 102 /* make sure that this structure is 4 byte aligned */ 103 uint8_t padding[2]; 104 char address[SCTP_ADDRMAX]; 105} SCTP_PACKED; 106 107 108/* draft-ietf-tsvwg-prsctp */ 109/* PR-SCTP supported parameter */ 110struct sctp_prsctp_supported_param { 111 struct sctp_paramhdr ph; 112} SCTP_PACKED; 113 114 115/* draft-ietf-tsvwg-addip-sctp */ 116struct sctp_asconf_paramhdr { /* an ASCONF "parameter" */ 117 struct sctp_paramhdr ph;/* a SCTP parameter header */ 118 uint32_t correlation_id;/* correlation id for this param */ 119} SCTP_PACKED; 120 121struct sctp_asconf_addr_param { /* an ASCONF address parameter */ 122 struct sctp_asconf_paramhdr aph; /* asconf "parameter" */ 123 struct sctp_ipv6addr_param addrp; /* max storage size */ 124} SCTP_PACKED; 125 126 127struct sctp_asconf_tag_param { /* an ASCONF NAT-Vtag parameter */ 128 struct sctp_asconf_paramhdr aph; /* asconf "parameter" */ 129 uint32_t local_vtag; 130 uint32_t remote_vtag; 131} SCTP_PACKED; 132 133 134struct sctp_asconf_addrv4_param { /* an ASCONF address (v4) parameter */ 135 struct sctp_asconf_paramhdr aph; /* asconf "parameter" */ 136 struct sctp_ipv4addr_param addrp; /* max storage size */ 137} SCTP_PACKED; 138 139#define SCTP_MAX_SUPPORTED_EXT 256 140 141struct sctp_supported_chunk_types_param { 142 struct sctp_paramhdr ph;/* type = 0x8008 len = x */ 143 uint8_t chunk_types[]; 144} SCTP_PACKED; 145 146 147/* 148 * Structures for DATA chunks 149 */ 150struct sctp_data { 151 uint32_t tsn; 152 uint16_t stream_id; 153 uint16_t stream_sequence; 154 uint32_t protocol_id; 155 /* user data follows */ 156} SCTP_PACKED; 157 158struct sctp_data_chunk { 159 struct sctp_chunkhdr ch; 160 struct sctp_data dp; 161} SCTP_PACKED; 162 163/* 164 * Structures for the control chunks 165 */ 166 167/* Initiate (INIT)/Initiate Ack (INIT ACK) */ 168struct sctp_init { 169 uint32_t initiate_tag; /* initiate tag */ 170 uint32_t a_rwnd; /* a_rwnd */ 171 uint16_t num_outbound_streams; /* OS */ 172 uint16_t num_inbound_streams; /* MIS */ 173 uint32_t initial_tsn; /* I-TSN */ 174 /* optional param's follow */ 175} SCTP_PACKED; 176 177#define SCTP_IDENTIFICATION_SIZE 16 178#define SCTP_ADDRESS_SIZE 4 179#define SCTP_RESERVE_SPACE 6 180/* state cookie header */ 181struct sctp_state_cookie { /* this is our definition... */ 182 uint8_t identification[SCTP_IDENTIFICATION_SIZE]; /* id of who we are */ 183 struct timeval time_entered; /* the time I built cookie */ 184 uint32_t cookie_life; /* life I will award this cookie */ 185 uint32_t tie_tag_my_vtag; /* my tag in old association */ 186 187 uint32_t tie_tag_peer_vtag; /* peers tag in old association */ 188 uint32_t peers_vtag; /* peers tag in INIT (for quick ref) */ 189 190 uint32_t my_vtag; /* my tag in INIT-ACK (for quick ref) */ 191 uint32_t address[SCTP_ADDRESS_SIZE]; /* 4 ints/128 bits */ 192 uint32_t addr_type; /* address type */ 193 uint32_t laddress[SCTP_ADDRESS_SIZE]; /* my local from address */ 194 uint32_t laddr_type; /* my local from address type */ 195 uint32_t scope_id; /* v6 scope id for link-locals */ 196 197 uint16_t peerport; /* port address of the peer in the INIT */ 198 uint16_t myport; /* my port address used in the INIT */ 199 uint8_t ipv4_addr_legal;/* Are V4 addr legal? */ 200 uint8_t ipv6_addr_legal;/* Are V6 addr legal? */ 201 uint8_t local_scope; /* IPv6 local scope flag */ 202 uint8_t site_scope; /* IPv6 site scope flag */ 203 204 uint8_t ipv4_scope; /* IPv4 private addr scope */ 205 uint8_t loopback_scope; /* loopback scope information */ 206 uint8_t reserved[SCTP_RESERVE_SPACE]; /* Align to 64 bits */ 207 /* 208 * at the end is tacked on the INIT chunk and the INIT-ACK chunk 209 * (minus the cookie). 210 */ 211} SCTP_PACKED; 212 213 214/* Used for NAT state error cause */ 215struct sctp_missing_nat_state { 216 uint16_t cause; 217 uint16_t length; 218 uint8_t data[]; 219} SCTP_PACKED; 220 221 222struct sctp_inv_mandatory_param { 223 uint16_t cause; 224 uint16_t length; 225 uint32_t num_param; 226 uint16_t param; 227 /* 228 * We include this to 0 it since only a missing cookie will cause 229 * this error. 230 */ 231 uint16_t resv; 232} SCTP_PACKED; 233 234struct sctp_unresolv_addr { 235 uint16_t cause; 236 uint16_t length; 237 uint16_t addr_type; 238 uint16_t reserved; /* Only one invalid addr type */ 239} SCTP_PACKED; 240 241/* state cookie parameter */ 242struct sctp_state_cookie_param { 243 struct sctp_paramhdr ph; 244 struct sctp_state_cookie cookie; 245} SCTP_PACKED; 246 247struct sctp_init_chunk { 248 struct sctp_chunkhdr ch; 249 struct sctp_init init; 250} SCTP_PACKED; 251 252struct sctp_init_msg { 253 struct sctphdr sh; 254 struct sctp_init_chunk msg; 255} SCTP_PACKED; 256 257/* ... used for both INIT and INIT ACK */ 258#define sctp_init_ack sctp_init 259#define sctp_init_ack_chunk sctp_init_chunk 260#define sctp_init_ack_msg sctp_init_msg 261 262 263/* Selective Ack (SACK) */ 264struct sctp_gap_ack_block { 265 uint16_t start; /* Gap Ack block start */ 266 uint16_t end; /* Gap Ack block end */ 267} SCTP_PACKED; 268 269struct sctp_sack { 270 uint32_t cum_tsn_ack; /* cumulative TSN Ack */ 271 uint32_t a_rwnd; /* updated a_rwnd of sender */ 272 uint16_t num_gap_ack_blks; /* number of Gap Ack blocks */ 273 uint16_t num_dup_tsns; /* number of duplicate TSNs */ 274 /* struct sctp_gap_ack_block's follow */ 275 /* uint32_t duplicate_tsn's follow */ 276} SCTP_PACKED; 277 278struct sctp_sack_chunk { 279 struct sctp_chunkhdr ch; 280 struct sctp_sack sack; 281} SCTP_PACKED; 282 283struct sctp_nr_sack { 284 uint32_t cum_tsn_ack; /* cumulative TSN Ack */ 285 uint32_t a_rwnd; /* updated a_rwnd of sender */ 286 uint16_t num_gap_ack_blks; /* number of Gap Ack blocks */ 287 uint16_t num_nr_gap_ack_blks; /* number of NR Gap Ack blocks */ 288 uint16_t num_dup_tsns; /* number of duplicate TSNs */ 289 uint16_t reserved; /* not currently used */ 290 /* struct sctp_gap_ack_block's follow */ 291 /* uint32_t duplicate_tsn's follow */ 292} SCTP_PACKED; 293 294struct sctp_nr_sack_chunk { 295 struct sctp_chunkhdr ch; 296 struct sctp_nr_sack nr_sack; 297} SCTP_PACKED; 298 299 300/* Heartbeat Request (HEARTBEAT) */ 301struct sctp_heartbeat { 302 struct sctp_heartbeat_info_param hb_info; 303} SCTP_PACKED; 304 305struct sctp_heartbeat_chunk { 306 struct sctp_chunkhdr ch; 307 struct sctp_heartbeat heartbeat; 308} SCTP_PACKED; 309 310/* ... used for Heartbeat Ack (HEARTBEAT ACK) */ 311#define sctp_heartbeat_ack sctp_heartbeat 312#define sctp_heartbeat_ack_chunk sctp_heartbeat_chunk 313 314 315/* Abort Asssociation (ABORT) */ 316struct sctp_abort_chunk { 317 struct sctp_chunkhdr ch; 318 /* optional error cause may follow */ 319} SCTP_PACKED; 320 321struct sctp_abort_msg { 322 struct sctphdr sh; 323 struct sctp_abort_chunk msg; 324} SCTP_PACKED; 325 326 327/* Shutdown Association (SHUTDOWN) */ 328struct sctp_shutdown_chunk { 329 struct sctp_chunkhdr ch; 330 uint32_t cumulative_tsn_ack; 331} SCTP_PACKED; 332 333 334/* Shutdown Acknowledgment (SHUTDOWN ACK) */ 335struct sctp_shutdown_ack_chunk { 336 struct sctp_chunkhdr ch; 337} SCTP_PACKED; 338 339 340/* Operation Error (ERROR) */ 341struct sctp_error_chunk { 342 struct sctp_chunkhdr ch; 343 /* optional error causes follow */ 344} SCTP_PACKED; 345 346 347/* Cookie Echo (COOKIE ECHO) */ 348struct sctp_cookie_echo_chunk { 349 struct sctp_chunkhdr ch; 350 struct sctp_state_cookie cookie; 351} SCTP_PACKED; 352 353/* Cookie Acknowledgment (COOKIE ACK) */ 354struct sctp_cookie_ack_chunk { 355 struct sctp_chunkhdr ch; 356} SCTP_PACKED; 357 358/* Explicit Congestion Notification Echo (ECNE) */ 359struct old_sctp_ecne_chunk { 360 struct sctp_chunkhdr ch; 361 uint32_t tsn; 362} SCTP_PACKED; 363 364struct sctp_ecne_chunk { 365 struct sctp_chunkhdr ch; 366 uint32_t tsn; 367 uint32_t num_pkts_since_cwr; 368} SCTP_PACKED; 369 370/* Congestion Window Reduced (CWR) */ 371struct sctp_cwr_chunk { 372 struct sctp_chunkhdr ch; 373 uint32_t tsn; 374} SCTP_PACKED; 375 376/* Shutdown Complete (SHUTDOWN COMPLETE) */ 377struct sctp_shutdown_complete_chunk { 378 struct sctp_chunkhdr ch; 379} SCTP_PACKED; 380 381/* Oper error holding a stale cookie */ 382struct sctp_stale_cookie_msg { 383 struct sctp_paramhdr ph;/* really an error cause */ 384 uint32_t time_usec; 385} SCTP_PACKED; 386 387struct sctp_adaptation_layer_indication { 388 struct sctp_paramhdr ph; 389 uint32_t indication; 390} SCTP_PACKED; 391 392struct sctp_cookie_while_shutting_down { 393 struct sctphdr sh; 394 struct sctp_chunkhdr ch; 395 struct sctp_paramhdr ph;/* really an error cause */ 396} SCTP_PACKED; 397 398struct sctp_shutdown_complete_msg { 399 struct sctphdr sh; 400 struct sctp_shutdown_complete_chunk shut_cmp; 401} SCTP_PACKED; 402 403/* 404 * draft-ietf-tsvwg-addip-sctp 405 */ 406/* Address/Stream Configuration Change (ASCONF) */ 407struct sctp_asconf_chunk { 408 struct sctp_chunkhdr ch; 409 uint32_t serial_number; 410 /* lookup address parameter (mandatory) */ 411 /* asconf parameters follow */ 412} SCTP_PACKED; 413 414/* Address/Stream Configuration Acknowledge (ASCONF ACK) */ 415struct sctp_asconf_ack_chunk { 416 struct sctp_chunkhdr ch; 417 uint32_t serial_number; 418 /* asconf parameters follow */ 419} SCTP_PACKED; 420 421/* draft-ietf-tsvwg-prsctp */ 422/* Forward Cumulative TSN (FORWARD TSN) */ 423struct sctp_forward_tsn_chunk { 424 struct sctp_chunkhdr ch; 425 uint32_t new_cumulative_tsn; 426 /* stream/sequence pairs (sctp_strseq) follow */ 427} SCTP_PACKED; 428 429struct sctp_strseq { 430 uint16_t stream; 431 uint16_t sequence; 432} SCTP_PACKED; 433 434struct sctp_forward_tsn_msg { 435 struct sctphdr sh; 436 struct sctp_forward_tsn_chunk msg; 437} SCTP_PACKED; 438 439/* should be a multiple of 4 - 1 aka 3/7/11 etc. */ 440 441#define SCTP_NUM_DB_TO_VERIFY 31 442 443struct sctp_chunk_desc { 444 uint8_t chunk_type; 445 uint8_t data_bytes[SCTP_NUM_DB_TO_VERIFY]; 446 uint32_t tsn_ifany; 447} SCTP_PACKED; 448 449 450struct sctp_pktdrop_chunk { 451 struct sctp_chunkhdr ch; 452 uint32_t bottle_bw; 453 uint32_t current_onq; 454 uint16_t trunc_len; 455 uint16_t reserved; 456 uint8_t data[]; 457} SCTP_PACKED; 458 459/**********STREAM RESET STUFF ******************/ 460 461struct sctp_stream_reset_out_request { 462 struct sctp_paramhdr ph; 463 uint32_t request_seq; /* monotonically increasing seq no */ 464 uint32_t response_seq; /* if a response, the resp seq no */ 465 uint32_t send_reset_at_tsn; /* last TSN I assigned outbound */ 466 uint16_t list_of_streams[]; /* if not all list of streams */ 467} SCTP_PACKED; 468 469struct sctp_stream_reset_in_request { 470 struct sctp_paramhdr ph; 471 uint32_t request_seq; 472 uint16_t list_of_streams[]; /* if not all list of streams */ 473} SCTP_PACKED; 474 475 476struct sctp_stream_reset_tsn_request { 477 struct sctp_paramhdr ph; 478 uint32_t request_seq; 479} SCTP_PACKED; 480 481struct sctp_stream_reset_response { 482 struct sctp_paramhdr ph; 483 uint32_t response_seq; /* if a response, the resp seq no */ 484 uint32_t result; 485} SCTP_PACKED; 486 487struct sctp_stream_reset_response_tsn { 488 struct sctp_paramhdr ph; 489 uint32_t response_seq; /* if a response, the resp seq no */ 490 uint32_t result; 491 uint32_t senders_next_tsn; 492 uint32_t receivers_next_tsn; 493} SCTP_PACKED; 494 495struct sctp_stream_reset_add_strm { 496 struct sctp_paramhdr ph; 497 uint32_t request_seq; 498 uint16_t number_of_streams; 499 uint16_t reserved; 500} SCTP_PACKED; 501 502#define SCTP_STREAM_RESET_NOTHING 0x00000000 /* Nothing for me to do */ 503#define SCTP_STREAM_RESET_PERFORMED 0x00000001 /* Did it */ 504#define SCTP_STREAM_RESET_DENIED 0x00000002 /* refused to do it */ 505#define SCTP_STREAM_RESET_ERROR_STR 0x00000003 /* bad Stream no */ 506#define SCTP_STREAM_RESET_TRY_LATER 0x00000004 /* collision, try again */ 507#define SCTP_STREAM_RESET_BAD_SEQNO 0x00000005 /* bad str-reset seq no */ 508 509/* 510 * convience structures, note that if you are making a request for specific 511 * streams then the request will need to be an overlay structure. 512 */ 513 514struct sctp_stream_reset_out_req { 515 struct sctp_chunkhdr ch; 516 struct sctp_stream_reset_out_request sr_req; 517} SCTP_PACKED; 518 519struct sctp_stream_reset_in_req { 520 struct sctp_chunkhdr ch; 521 struct sctp_stream_reset_in_request sr_req; 522} SCTP_PACKED; 523 524struct sctp_stream_reset_tsn_req { 525 struct sctp_chunkhdr ch; 526 struct sctp_stream_reset_tsn_request sr_req; 527} SCTP_PACKED; 528 529struct sctp_stream_reset_resp { 530 struct sctp_chunkhdr ch; 531 struct sctp_stream_reset_response sr_resp; 532} SCTP_PACKED; 533 534/* respone only valid with a TSN request */ 535struct sctp_stream_reset_resp_tsn { 536 struct sctp_chunkhdr ch; 537 struct sctp_stream_reset_response_tsn sr_resp; 538} SCTP_PACKED; 539 540/****************************************************/ 541 542/* 543 * Authenticated chunks support draft-ietf-tsvwg-sctp-auth 544 */ 545 546/* Should we make the max be 32? */ 547#define SCTP_RANDOM_MAX_SIZE 256 548struct sctp_auth_random { 549 struct sctp_paramhdr ph;/* type = 0x8002 */ 550 uint8_t random_data[]; 551} SCTP_PACKED; 552 553struct sctp_auth_chunk_list { 554 struct sctp_paramhdr ph;/* type = 0x8003 */ 555 uint8_t chunk_types[]; 556} SCTP_PACKED; 557 558struct sctp_auth_hmac_algo { 559 struct sctp_paramhdr ph;/* type = 0x8004 */ 560 uint16_t hmac_ids[]; 561} SCTP_PACKED; 562 563struct sctp_auth_chunk { 564 struct sctp_chunkhdr ch; 565 uint16_t shared_key_id; 566 uint16_t hmac_id; 567 uint8_t hmac[]; 568} SCTP_PACKED; 569 570struct sctp_auth_invalid_hmac { 571 struct sctp_paramhdr ph; 572 uint16_t hmac_id; 573 uint16_t padding; 574} SCTP_PACKED; 575 576/* 577 * we pre-reserve enough room for a ECNE or CWR AND a SACK with no missing 578 * pieces. If ENCE is missing we could have a couple of blocks. This way we 579 * optimize so we MOST likely can bundle a SACK/ECN with the smallest size 580 * data chunk I will split into. We could increase throughput slightly by 581 * taking out these two but the 24-sack/8-CWR i.e. 32 bytes I pre-reserve I 582 * feel is worth it for now. 583 */ 584#ifndef SCTP_MAX_OVERHEAD 585#ifdef INET6 586#define SCTP_MAX_OVERHEAD (sizeof(struct sctp_data_chunk) + \ 587 sizeof(struct sctphdr) + \ 588 sizeof(struct sctp_ecne_chunk) + \ 589 sizeof(struct sctp_sack_chunk) + \ 590 sizeof(struct ip6_hdr)) 591 592#define SCTP_MED_OVERHEAD (sizeof(struct sctp_data_chunk) + \ 593 sizeof(struct sctphdr) + \ 594 sizeof(struct ip6_hdr)) 595 596 597#define SCTP_MIN_OVERHEAD (sizeof(struct ip6_hdr) + \ 598 sizeof(struct sctphdr)) 599 600#else 601#define SCTP_MAX_OVERHEAD (sizeof(struct sctp_data_chunk) + \ 602 sizeof(struct sctphdr) + \ 603 sizeof(struct sctp_ecne_chunk) + \ 604 sizeof(struct sctp_sack_chunk) + \ 605 sizeof(struct ip)) 606 607#define SCTP_MED_OVERHEAD (sizeof(struct sctp_data_chunk) + \ 608 sizeof(struct sctphdr) + \ 609 sizeof(struct ip)) 610 611 612#define SCTP_MIN_OVERHEAD (sizeof(struct ip) + \ 613 sizeof(struct sctphdr)) 614 615#endif /* INET6 */ 616#endif /* !SCTP_MAX_OVERHEAD */ 617 618#define SCTP_MED_V4_OVERHEAD (sizeof(struct sctp_data_chunk) + \ 619 sizeof(struct sctphdr) + \ 620 sizeof(struct ip)) 621 622#define SCTP_MIN_V4_OVERHEAD (sizeof(struct ip) + \ 623 sizeof(struct sctphdr)) 624 625#undef SCTP_PACKED 626#endif /* !__sctp_header_h__ */ 627