sctp_header.h revision 188854
1/*- 2 * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are met: 6 * 7 * a) Redistributions of source code must retain the above copyright notice, 8 * this list of conditions and the following disclaimer. 9 * 10 * b) Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the distribution. 13 * 14 * c) Neither the name of Cisco Systems, Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived 16 * from this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 20 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 28 * THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31/* $KAME: sctp_header.h,v 1.14 2005/03/06 16:04:17 itojun Exp $ */ 32 33#include <sys/cdefs.h> 34__FBSDID("$FreeBSD: head/sys/netinet/sctp_header.h 188854 2009-02-20 15:03:54Z rrs $"); 35 36#ifndef __sctp_header_h__ 37#define __sctp_header_h__ 38 39#include <sys/time.h> 40#include <netinet/sctp.h> 41#include <netinet/sctp_constants.h> 42 43#define SCTP_PACKED __attribute__((packed)) 44 45/* 46 * Parameter structures 47 */ 48struct sctp_ipv4addr_param { 49 struct sctp_paramhdr ph;/* type=SCTP_IPV4_PARAM_TYPE, len=8 */ 50 uint32_t addr; /* IPV4 address */ 51} SCTP_PACKED; 52 53#define SCTP_V6_ADDR_BYTES 16 54 55 56struct sctp_ipv6addr_param { 57 struct sctp_paramhdr ph;/* type=SCTP_IPV6_PARAM_TYPE, len=20 */ 58 uint8_t addr[SCTP_V6_ADDR_BYTES]; /* IPV6 address */ 59} SCTP_PACKED; 60 61/* Cookie Preservative */ 62struct sctp_cookie_perserve_param { 63 struct sctp_paramhdr ph;/* type=SCTP_COOKIE_PRESERVE, len=8 */ 64 uint32_t time; /* time in ms to extend cookie */ 65}; 66 67#define SCTP_ARRAY_MIN_LEN 1 68/* Host Name Address */ 69struct sctp_host_name_param { 70 struct sctp_paramhdr ph;/* type=SCTP_HOSTNAME_ADDRESS */ 71 char name[SCTP_ARRAY_MIN_LEN]; /* host name */ 72} SCTP_PACKED; 73 74/* 75 * This is the maximum padded size of a s-a-p 76 * so paramheadr + 3 address types (6 bytes) + 2 byte pad = 12 77 */ 78#define SCTP_MAX_ADDR_PARAMS_SIZE 12 79/* supported address type */ 80struct sctp_supported_addr_param { 81 struct sctp_paramhdr ph;/* type=SCTP_SUPPORTED_ADDRTYPE */ 82 uint16_t addr_type[SCTP_ARRAY_MIN_LEN]; /* array of supported address 83 * types */ 84} SCTP_PACKED; 85 86/* ECN parameter */ 87struct sctp_ecn_supported_param { 88 struct sctp_paramhdr ph;/* type=SCTP_ECN_CAPABLE */ 89} SCTP_PACKED; 90 91 92/* heartbeat info parameter */ 93struct sctp_heartbeat_info_param { 94 struct sctp_paramhdr ph; 95 uint32_t time_value_1; 96 uint32_t time_value_2; 97 uint32_t random_value1; 98 uint32_t random_value2; 99 uint16_t user_req; 100 uint8_t addr_family; 101 uint8_t addr_len; 102 char address[SCTP_ADDRMAX]; 103} SCTP_PACKED; 104 105 106/* draft-ietf-tsvwg-prsctp */ 107/* PR-SCTP supported parameter */ 108struct sctp_prsctp_supported_param { 109 struct sctp_paramhdr ph; 110} SCTP_PACKED; 111 112 113/* draft-ietf-tsvwg-addip-sctp */ 114struct sctp_asconf_paramhdr { /* an ASCONF "parameter" */ 115 struct sctp_paramhdr ph;/* a SCTP parameter header */ 116 uint32_t correlation_id;/* correlation id for this param */ 117} SCTP_PACKED; 118 119struct sctp_asconf_addr_param { /* an ASCONF address parameter */ 120 struct sctp_asconf_paramhdr aph; /* asconf "parameter" */ 121 struct sctp_ipv6addr_param addrp; /* max storage size */ 122} SCTP_PACKED; 123 124 125struct sctp_asconf_tag_param { /* an ASCONF NAT-Vtag parameter */ 126 struct sctp_asconf_paramhdr aph; /* asconf "parameter" */ 127 uint32_t local_vtag; 128 uint32_t remote_vtag; 129} SCTP_PACKED; 130 131 132struct sctp_asconf_addrv4_param { /* an ASCONF address (v4) parameter */ 133 struct sctp_asconf_paramhdr aph; /* asconf "parameter" */ 134 struct sctp_ipv4addr_param addrp; /* max storage size */ 135} SCTP_PACKED; 136 137#define SCTP_MAX_SUPPORTED_EXT 256 138 139struct sctp_supported_chunk_types_param { 140 struct sctp_paramhdr ph;/* type = 0x8008 len = x */ 141 uint8_t chunk_types[0]; 142} SCTP_PACKED; 143 144 145/* ECN Nonce: draft-ladha-sctp-ecn-nonce */ 146struct sctp_ecn_nonce_supported_param { 147 struct sctp_paramhdr ph;/* type = 0x8001 len = 4 */ 148} SCTP_PACKED; 149 150 151/* 152 * Structures for DATA chunks 153 */ 154struct sctp_data { 155 uint32_t tsn; 156 uint16_t stream_id; 157 uint16_t stream_sequence; 158 uint32_t protocol_id; 159 /* user data follows */ 160} SCTP_PACKED; 161 162struct sctp_data_chunk { 163 struct sctp_chunkhdr ch; 164 struct sctp_data dp; 165} SCTP_PACKED; 166 167/* 168 * Structures for the control chunks 169 */ 170 171/* Initiate (INIT)/Initiate Ack (INIT ACK) */ 172struct sctp_init { 173 uint32_t initiate_tag; /* initiate tag */ 174 uint32_t a_rwnd; /* a_rwnd */ 175 uint16_t num_outbound_streams; /* OS */ 176 uint16_t num_inbound_streams; /* MIS */ 177 uint32_t initial_tsn; /* I-TSN */ 178 /* optional param's follow */ 179} SCTP_PACKED; 180 181#define SCTP_IDENTIFICATION_SIZE 16 182#define SCTP_ADDRESS_SIZE 4 183#define SCTP_RESERVE_SPACE 6 184/* state cookie header */ 185struct sctp_state_cookie { /* this is our definition... */ 186 uint8_t identification[SCTP_IDENTIFICATION_SIZE]; /* id of who we are */ 187 struct timeval time_entered; /* the time I built cookie */ 188 uint32_t cookie_life; /* life I will award this cookie */ 189 uint32_t tie_tag_my_vtag; /* my tag in old association */ 190 191 uint32_t tie_tag_peer_vtag; /* peers tag in old association */ 192 uint32_t peers_vtag; /* peers tag in INIT (for quick ref) */ 193 194 uint32_t my_vtag; /* my tag in INIT-ACK (for quick ref) */ 195 uint32_t address[SCTP_ADDRESS_SIZE]; /* 4 ints/128 bits */ 196 uint32_t addr_type; /* address type */ 197 uint32_t laddress[SCTP_ADDRESS_SIZE]; /* my local from address */ 198 uint32_t laddr_type; /* my local from address type */ 199 uint32_t scope_id; /* v6 scope id for link-locals */ 200 201 uint16_t peerport; /* port address of the peer in the INIT */ 202 uint16_t myport; /* my port address used in the INIT */ 203 uint8_t ipv4_addr_legal;/* Are V4 addr legal? */ 204 uint8_t ipv6_addr_legal;/* Are V6 addr legal? */ 205 uint8_t local_scope; /* IPv6 local scope flag */ 206 uint8_t site_scope; /* IPv6 site scope flag */ 207 208 uint8_t ipv4_scope; /* IPv4 private addr scope */ 209 uint8_t loopback_scope; /* loopback scope information */ 210 uint8_t reserved[SCTP_RESERVE_SPACE]; /* Align to 64 bits */ 211 /* 212 * at the end is tacked on the INIT chunk and the INIT-ACK chunk 213 * (minus the cookie). 214 */ 215} SCTP_PACKED; 216 217 218/* Used for NAT state error cause */ 219struct sctp_missing_nat_state { 220 uint16_t cause; 221 uint16_t length; 222 uint8_t data[0]; 223} SCTP_PACKED; 224 225 226struct sctp_inv_mandatory_param { 227 uint16_t cause; 228 uint16_t length; 229 uint32_t num_param; 230 uint16_t param; 231 /* 232 * We include this to 0 it since only a missing cookie will cause 233 * this error. 234 */ 235 uint16_t resv; 236} SCTP_PACKED; 237 238struct sctp_unresolv_addr { 239 uint16_t cause; 240 uint16_t length; 241 uint16_t addr_type; 242 uint16_t reserved; /* Only one invalid addr type */ 243} SCTP_PACKED; 244 245/* state cookie parameter */ 246struct sctp_state_cookie_param { 247 struct sctp_paramhdr ph; 248 struct sctp_state_cookie cookie; 249} SCTP_PACKED; 250 251struct sctp_init_chunk { 252 struct sctp_chunkhdr ch; 253 struct sctp_init init; 254} SCTP_PACKED; 255 256struct sctp_init_msg { 257 struct sctphdr sh; 258 struct sctp_init_chunk msg; 259} SCTP_PACKED; 260 261/* ... used for both INIT and INIT ACK */ 262#define sctp_init_ack sctp_init 263#define sctp_init_ack_chunk sctp_init_chunk 264#define sctp_init_ack_msg sctp_init_msg 265 266 267/* Selective Ack (SACK) */ 268struct sctp_gap_ack_block { 269 uint16_t start; /* Gap Ack block start */ 270 uint16_t end; /* Gap Ack block end */ 271} SCTP_PACKED; 272 273struct sctp_sack { 274 uint32_t cum_tsn_ack; /* cumulative TSN Ack */ 275 uint32_t a_rwnd; /* updated a_rwnd of sender */ 276 uint16_t num_gap_ack_blks; /* number of Gap Ack blocks */ 277 uint16_t num_dup_tsns; /* number of duplicate TSNs */ 278 /* struct sctp_gap_ack_block's follow */ 279 /* uint32_t duplicate_tsn's follow */ 280} SCTP_PACKED; 281 282struct sctp_sack_chunk { 283 struct sctp_chunkhdr ch; 284 struct sctp_sack sack; 285} SCTP_PACKED; 286 287 288/* EY Following 3 structs define NR Selective Ack (NR_SACK) chunk */ 289struct sctp_nr_gap_ack_block { 290 uint16_t start; /* NR Gap Ack block start */ 291 uint16_t end; /* NR Gap Ack block end */ 292} SCTP_PACKED; 293 294struct sctp_nr_sack { 295 uint32_t cum_tsn_ack; /* cumulative TSN Ack */ 296 uint32_t a_rwnd; /* updated a_rwnd of sender */ 297 uint16_t num_gap_ack_blks; /* number of Gap Ack blocks */ 298 uint16_t num_nr_gap_ack_blks; /* number of NR Gap Ack blocks */ 299 uint16_t num_dup_tsns; /* number of duplicate TSNs */ 300 uint16_t reserved; /* not currently used */ 301 /* struct sctp_gap_ack_block's follow */ 302 /* struct sctp_nr_gap_ack_block's follow */ 303 /* uint32_t duplicate_tsn's follow */ 304} SCTP_PACKED; 305 306struct sctp_nr_sack_chunk { 307 struct sctp_chunkhdr ch; 308 struct sctp_nr_sack nr_sack; 309} SCTP_PACKED; 310 311 312/* Heartbeat Request (HEARTBEAT) */ 313struct sctp_heartbeat { 314 struct sctp_heartbeat_info_param hb_info; 315} SCTP_PACKED; 316 317struct sctp_heartbeat_chunk { 318 struct sctp_chunkhdr ch; 319 struct sctp_heartbeat heartbeat; 320} SCTP_PACKED; 321 322/* ... used for Heartbeat Ack (HEARTBEAT ACK) */ 323#define sctp_heartbeat_ack sctp_heartbeat 324#define sctp_heartbeat_ack_chunk sctp_heartbeat_chunk 325 326 327/* Abort Asssociation (ABORT) */ 328struct sctp_abort_chunk { 329 struct sctp_chunkhdr ch; 330 /* optional error cause may follow */ 331} SCTP_PACKED; 332 333struct sctp_abort_msg { 334 struct sctphdr sh; 335 struct sctp_abort_chunk msg; 336} SCTP_PACKED; 337 338 339/* Shutdown Association (SHUTDOWN) */ 340struct sctp_shutdown_chunk { 341 struct sctp_chunkhdr ch; 342 uint32_t cumulative_tsn_ack; 343} SCTP_PACKED; 344 345 346/* Shutdown Acknowledgment (SHUTDOWN ACK) */ 347struct sctp_shutdown_ack_chunk { 348 struct sctp_chunkhdr ch; 349} SCTP_PACKED; 350 351 352/* Operation Error (ERROR) */ 353struct sctp_error_chunk { 354 struct sctp_chunkhdr ch; 355 /* optional error causes follow */ 356} SCTP_PACKED; 357 358 359/* Cookie Echo (COOKIE ECHO) */ 360struct sctp_cookie_echo_chunk { 361 struct sctp_chunkhdr ch; 362 struct sctp_state_cookie cookie; 363} SCTP_PACKED; 364 365/* Cookie Acknowledgment (COOKIE ACK) */ 366struct sctp_cookie_ack_chunk { 367 struct sctp_chunkhdr ch; 368} SCTP_PACKED; 369 370/* Explicit Congestion Notification Echo (ECNE) */ 371struct sctp_ecne_chunk { 372 struct sctp_chunkhdr ch; 373 uint32_t tsn; 374} SCTP_PACKED; 375 376/* Congestion Window Reduced (CWR) */ 377struct sctp_cwr_chunk { 378 struct sctp_chunkhdr ch; 379 uint32_t tsn; 380} SCTP_PACKED; 381 382/* Shutdown Complete (SHUTDOWN COMPLETE) */ 383struct sctp_shutdown_complete_chunk { 384 struct sctp_chunkhdr ch; 385} SCTP_PACKED; 386 387/* Oper error holding a stale cookie */ 388struct sctp_stale_cookie_msg { 389 struct sctp_paramhdr ph;/* really an error cause */ 390 uint32_t time_usec; 391} SCTP_PACKED; 392 393struct sctp_adaptation_layer_indication { 394 struct sctp_paramhdr ph; 395 uint32_t indication; 396} SCTP_PACKED; 397 398struct sctp_cookie_while_shutting_down { 399 struct sctphdr sh; 400 struct sctp_chunkhdr ch; 401 struct sctp_paramhdr ph;/* really an error cause */ 402} SCTP_PACKED; 403 404struct sctp_shutdown_complete_msg { 405 struct sctphdr sh; 406 struct sctp_shutdown_complete_chunk shut_cmp; 407} SCTP_PACKED; 408 409/* 410 * draft-ietf-tsvwg-addip-sctp 411 */ 412/* Address/Stream Configuration Change (ASCONF) */ 413struct sctp_asconf_chunk { 414 struct sctp_chunkhdr ch; 415 uint32_t serial_number; 416 /* lookup address parameter (mandatory) */ 417 /* asconf parameters follow */ 418} SCTP_PACKED; 419 420/* Address/Stream Configuration Acknowledge (ASCONF ACK) */ 421struct sctp_asconf_ack_chunk { 422 struct sctp_chunkhdr ch; 423 uint32_t serial_number; 424 /* asconf parameters follow */ 425} SCTP_PACKED; 426 427/* draft-ietf-tsvwg-prsctp */ 428/* Forward Cumulative TSN (FORWARD TSN) */ 429struct sctp_forward_tsn_chunk { 430 struct sctp_chunkhdr ch; 431 uint32_t new_cumulative_tsn; 432 /* stream/sequence pairs (sctp_strseq) follow */ 433} SCTP_PACKED; 434 435struct sctp_strseq { 436 uint16_t stream; 437 uint16_t sequence; 438} SCTP_PACKED; 439 440struct sctp_forward_tsn_msg { 441 struct sctphdr sh; 442 struct sctp_forward_tsn_chunk msg; 443} SCTP_PACKED; 444 445/* should be a multiple of 4 - 1 aka 3/7/11 etc. */ 446 447#define SCTP_NUM_DB_TO_VERIFY 31 448 449struct sctp_chunk_desc { 450 uint8_t chunk_type; 451 uint8_t data_bytes[SCTP_NUM_DB_TO_VERIFY]; 452 uint32_t tsn_ifany; 453} SCTP_PACKED; 454 455 456struct sctp_pktdrop_chunk { 457 struct sctp_chunkhdr ch; 458 uint32_t bottle_bw; 459 uint32_t current_onq; 460 uint16_t trunc_len; 461 uint16_t reserved; 462 uint8_t data[0]; 463} SCTP_PACKED; 464 465/**********STREAM RESET STUFF ******************/ 466 467struct sctp_stream_reset_out_request { 468 struct sctp_paramhdr ph; 469 uint32_t request_seq; /* monotonically increasing seq no */ 470 uint32_t response_seq; /* if a response, the resp seq no */ 471 uint32_t send_reset_at_tsn; /* last TSN I assigned outbound */ 472 uint16_t list_of_streams[0]; /* if not all list of streams */ 473} SCTP_PACKED; 474 475struct sctp_stream_reset_in_request { 476 struct sctp_paramhdr ph; 477 uint32_t request_seq; 478 uint16_t list_of_streams[0]; /* if not all list of streams */ 479} SCTP_PACKED; 480 481 482struct sctp_stream_reset_tsn_request { 483 struct sctp_paramhdr ph; 484 uint32_t request_seq; 485} SCTP_PACKED; 486 487struct sctp_stream_reset_response { 488 struct sctp_paramhdr ph; 489 uint32_t response_seq; /* if a response, the resp seq no */ 490 uint32_t result; 491} SCTP_PACKED; 492 493struct sctp_stream_reset_response_tsn { 494 struct sctp_paramhdr ph; 495 uint32_t response_seq; /* if a response, the resp seq no */ 496 uint32_t result; 497 uint32_t senders_next_tsn; 498 uint32_t receivers_next_tsn; 499} SCTP_PACKED; 500 501struct sctp_stream_reset_add_strm { 502 struct sctp_paramhdr ph; 503 uint32_t request_seq; 504 uint16_t number_of_streams; 505 uint16_t reserved; 506}; 507 508#define SCTP_STREAM_RESET_NOTHING 0x00000000 /* Nothing for me to do */ 509#define SCTP_STREAM_RESET_PERFORMED 0x00000001 /* Did it */ 510#define SCTP_STREAM_RESET_DENIED 0x00000002 /* refused to do it */ 511#define SCTP_STREAM_RESET_ERROR_STR 0x00000003 /* bad Stream no */ 512#define SCTP_STREAM_RESET_TRY_LATER 0x00000004 /* collision, try again */ 513#define SCTP_STREAM_RESET_BAD_SEQNO 0x00000005 /* bad str-reset seq no */ 514 515/* 516 * convience structures, note that if you are making a request for specific 517 * streams then the request will need to be an overlay structure. 518 */ 519 520struct sctp_stream_reset_out_req { 521 struct sctp_chunkhdr ch; 522 struct sctp_stream_reset_out_request sr_req; 523} SCTP_PACKED; 524 525struct sctp_stream_reset_in_req { 526 struct sctp_chunkhdr ch; 527 struct sctp_stream_reset_in_request sr_req; 528} SCTP_PACKED; 529 530struct sctp_stream_reset_tsn_req { 531 struct sctp_chunkhdr ch; 532 struct sctp_stream_reset_tsn_request sr_req; 533} SCTP_PACKED; 534 535struct sctp_stream_reset_resp { 536 struct sctp_chunkhdr ch; 537 struct sctp_stream_reset_response sr_resp; 538} SCTP_PACKED; 539 540/* respone only valid with a TSN request */ 541struct sctp_stream_reset_resp_tsn { 542 struct sctp_chunkhdr ch; 543 struct sctp_stream_reset_response_tsn sr_resp; 544} SCTP_PACKED; 545 546/****************************************************/ 547 548/* 549 * Authenticated chunks support draft-ietf-tsvwg-sctp-auth 550 */ 551 552/* Should we make the max be 32? */ 553#define SCTP_RANDOM_MAX_SIZE 256 554struct sctp_auth_random { 555 struct sctp_paramhdr ph;/* type = 0x8002 */ 556 uint8_t random_data[0]; 557} SCTP_PACKED; 558 559struct sctp_auth_chunk_list { 560 struct sctp_paramhdr ph;/* type = 0x8003 */ 561 uint8_t chunk_types[0]; 562} SCTP_PACKED; 563 564struct sctp_auth_hmac_algo { 565 struct sctp_paramhdr ph;/* type = 0x8004 */ 566 uint16_t hmac_ids[0]; 567} SCTP_PACKED; 568 569struct sctp_auth_chunk { 570 struct sctp_chunkhdr ch; 571 uint16_t shared_key_id; 572 uint16_t hmac_id; 573 uint8_t hmac[0]; 574} SCTP_PACKED; 575 576struct sctp_auth_invalid_hmac { 577 struct sctp_paramhdr ph; 578 uint16_t hmac_id; 579 uint16_t padding; 580} SCTP_PACKED; 581 582/* 583 * we pre-reserve enough room for a ECNE or CWR AND a SACK with no missing 584 * pieces. If ENCE is missing we could have a couple of blocks. This way we 585 * optimize so we MOST likely can bundle a SACK/ECN with the smallest size 586 * data chunk I will split into. We could increase throughput slightly by 587 * taking out these two but the 24-sack/8-CWR i.e. 32 bytes I pre-reserve I 588 * feel is worth it for now. 589 */ 590#ifndef SCTP_MAX_OVERHEAD 591#ifdef INET6 592#define SCTP_MAX_OVERHEAD (sizeof(struct sctp_data_chunk) + \ 593 sizeof(struct sctphdr) + \ 594 sizeof(struct sctp_ecne_chunk) + \ 595 sizeof(struct sctp_sack_chunk) + \ 596 sizeof(struct ip6_hdr)) 597 598#define SCTP_MED_OVERHEAD (sizeof(struct sctp_data_chunk) + \ 599 sizeof(struct sctphdr) + \ 600 sizeof(struct ip6_hdr)) 601 602 603#define SCTP_MIN_OVERHEAD (sizeof(struct ip6_hdr) + \ 604 sizeof(struct sctphdr)) 605 606#else 607#define SCTP_MAX_OVERHEAD (sizeof(struct sctp_data_chunk) + \ 608 sizeof(struct sctphdr) + \ 609 sizeof(struct sctp_ecne_chunk) + \ 610 sizeof(struct sctp_sack_chunk) + \ 611 sizeof(struct ip)) 612 613#define SCTP_MED_OVERHEAD (sizeof(struct sctp_data_chunk) + \ 614 sizeof(struct sctphdr) + \ 615 sizeof(struct ip)) 616 617 618#define SCTP_MIN_OVERHEAD (sizeof(struct ip) + \ 619 sizeof(struct sctphdr)) 620 621#endif /* INET6 */ 622#endif /* !SCTP_MAX_OVERHEAD */ 623 624#define SCTP_MED_V4_OVERHEAD (sizeof(struct sctp_data_chunk) + \ 625 sizeof(struct sctphdr) + \ 626 sizeof(struct ip)) 627 628#define SCTP_MIN_V4_OVERHEAD (sizeof(struct ip) + \ 629 sizeof(struct sctphdr)) 630 631#undef SCTP_PACKED 632#endif /* !__sctp_header_h__ */ 633