tcp_var.h revision 157376
1/*- 2 * Copyright (c) 1982, 1986, 1993, 1994, 1995 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)tcp_var.h 8.4 (Berkeley) 5/24/95 30 * $FreeBSD: head/sys/netinet/tcp_var.h 157376 2006-04-01 16:36:36Z rwatson $ 31 */ 32 33#ifndef _NETINET_TCP_VAR_H_ 34#define _NETINET_TCP_VAR_H_ 35 36#include <netinet/tcp.h> 37 38/* 39 * Kernel variables for tcp. 40 */ 41extern int tcp_do_rfc1323; 42 43/* TCP segment queue entry */ 44struct tseg_qent { 45 LIST_ENTRY(tseg_qent) tqe_q; 46 int tqe_len; /* TCP segment data length */ 47 struct tcphdr *tqe_th; /* a pointer to tcp header */ 48 struct mbuf *tqe_m; /* mbuf contains packet */ 49}; 50LIST_HEAD(tsegqe_head, tseg_qent); 51extern int tcp_reass_qsize; 52extern struct uma_zone *tcp_reass_zone; 53 54struct sackblk { 55 tcp_seq start; /* start seq no. of sack block */ 56 tcp_seq end; /* end seq no. */ 57}; 58 59struct sackhole { 60 tcp_seq start; /* start seq no. of hole */ 61 tcp_seq end; /* end seq no. */ 62 tcp_seq rxmit; /* next seq. no in hole to be retransmitted */ 63 TAILQ_ENTRY(sackhole) scblink; /* scoreboard linkage */ 64}; 65 66struct sackhint { 67 struct sackhole *nexthole; 68 int sack_bytes_rexmit; 69}; 70 71struct tcptemp { 72 u_char tt_ipgen[40]; /* the size must be of max ip header, now IPv6 */ 73 struct tcphdr tt_t; 74}; 75 76#define tcp6cb tcpcb /* for KAME src sync over BSD*'s */ 77 78/* 79 * Tcp control block, one per tcp; fields: 80 * Organized for 16 byte cacheline efficiency. 81 */ 82struct tcpcb { 83 struct tsegqe_head t_segq; /* segment reassembly queue */ 84 int t_segqlen; /* segment reassembly queue length */ 85 int t_dupacks; /* consecutive dup acks recd */ 86 87 struct callout *tt_rexmt; /* retransmit timer */ 88 struct callout *tt_persist; /* retransmit persistence */ 89 struct callout *tt_keep; /* keepalive */ 90 struct callout *tt_2msl; /* 2*msl TIME_WAIT timer */ 91 struct callout *tt_delack; /* delayed ACK timer */ 92 93 struct inpcb *t_inpcb; /* back pointer to internet pcb */ 94 int t_state; /* state of this connection */ 95 u_int t_flags; 96#define TF_ACKNOW 0x000001 /* ack peer immediately */ 97#define TF_DELACK 0x000002 /* ack, but try to delay it */ 98#define TF_NODELAY 0x000004 /* don't delay packets to coalesce */ 99#define TF_NOOPT 0x000008 /* don't use tcp options */ 100#define TF_SENTFIN 0x000010 /* have sent FIN */ 101#define TF_REQ_SCALE 0x000020 /* have/will request window scaling */ 102#define TF_RCVD_SCALE 0x000040 /* other side has requested scaling */ 103#define TF_REQ_TSTMP 0x000080 /* have/will request timestamps */ 104#define TF_RCVD_TSTMP 0x000100 /* a timestamp was received in SYN */ 105#define TF_SACK_PERMIT 0x000200 /* other side said I could SACK */ 106#define TF_NEEDSYN 0x000400 /* send SYN (implicit state) */ 107#define TF_NEEDFIN 0x000800 /* send FIN (implicit state) */ 108#define TF_NOPUSH 0x001000 /* don't push */ 109#define TF_MORETOCOME 0x010000 /* More data to be appended to sock */ 110#define TF_LQ_OVERFLOW 0x020000 /* listen queue overflow */ 111#define TF_LASTIDLE 0x040000 /* connection was previously idle */ 112#define TF_RXWIN0SENT 0x080000 /* sent a receiver win 0 in response */ 113#define TF_FASTRECOVERY 0x100000 /* in NewReno Fast Recovery */ 114#define TF_WASFRECOVERY 0x200000 /* was in NewReno Fast Recovery */ 115#define TF_SIGNATURE 0x400000 /* require MD5 digests (RFC2385) */ 116#define TF_FORCEDATA 0x800000 /* force out a byte */ 117 118 tcp_seq snd_una; /* send unacknowledged */ 119 tcp_seq snd_max; /* highest sequence number sent; 120 * used to recognize retransmits 121 */ 122 tcp_seq snd_nxt; /* send next */ 123 tcp_seq snd_up; /* send urgent pointer */ 124 125 tcp_seq snd_wl1; /* window update seg seq number */ 126 tcp_seq snd_wl2; /* window update seg ack number */ 127 tcp_seq iss; /* initial send sequence number */ 128 tcp_seq irs; /* initial receive sequence number */ 129 130 tcp_seq rcv_nxt; /* receive next */ 131 tcp_seq rcv_adv; /* advertised window */ 132 u_long rcv_wnd; /* receive window */ 133 tcp_seq rcv_up; /* receive urgent pointer */ 134 135 u_long snd_wnd; /* send window */ 136 u_long snd_cwnd; /* congestion-controlled window */ 137 u_long snd_bwnd; /* bandwidth-controlled window */ 138 u_long snd_ssthresh; /* snd_cwnd size threshold for 139 * for slow start exponential to 140 * linear switch 141 */ 142 u_long snd_bandwidth; /* calculated bandwidth or 0 */ 143 tcp_seq snd_recover; /* for use in NewReno Fast Recovery */ 144 145 u_int t_maxopd; /* mss plus options */ 146 147 u_long t_rcvtime; /* inactivity time */ 148 u_long t_starttime; /* time connection was established */ 149 int t_rtttime; /* round trip time */ 150 tcp_seq t_rtseq; /* sequence number being timed */ 151 152 int t_bw_rtttime; /* used for bandwidth calculation */ 153 tcp_seq t_bw_rtseq; /* used for bandwidth calculation */ 154 155 int t_rxtcur; /* current retransmit value (ticks) */ 156 u_int t_maxseg; /* maximum segment size */ 157 int t_srtt; /* smoothed round-trip time */ 158 int t_rttvar; /* variance in round-trip time */ 159 160 int t_rxtshift; /* log(2) of rexmt exp. backoff */ 161 u_int t_rttmin; /* minimum rtt allowed */ 162 u_int t_rttbest; /* best rtt we've seen */ 163 u_long t_rttupdated; /* number of times rtt sampled */ 164 u_long max_sndwnd; /* largest window peer has offered */ 165 166 int t_softerror; /* possible error not yet reported */ 167/* out-of-band data */ 168 char t_oobflags; /* have some */ 169 char t_iobc; /* input character */ 170#define TCPOOB_HAVEDATA 0x01 171#define TCPOOB_HADDATA 0x02 172/* RFC 1323 variables */ 173 u_char snd_scale; /* window scaling for send window */ 174 u_char rcv_scale; /* window scaling for recv window */ 175 u_char request_r_scale; /* pending window scaling */ 176 u_char requested_s_scale; /* unused, to be reused later */ 177 u_long ts_recent; /* timestamp echo data */ 178 179 u_long ts_recent_age; /* when last updated */ 180 tcp_seq last_ack_sent; 181/* experimental */ 182 u_long snd_cwnd_prev; /* cwnd prior to retransmit */ 183 u_long snd_ssthresh_prev; /* ssthresh prior to retransmit */ 184 tcp_seq snd_recover_prev; /* snd_recover prior to retransmit */ 185 u_long t_badrxtwin; /* window for retransmit recovery */ 186 u_char snd_limited; /* segments limited transmitted */ 187/* anti DoS counters */ 188 u_long rcv_second; /* start of interval second */ 189 u_long rcv_pps; /* received packets per second */ 190 u_long rcv_byps; /* received bytes per second */ 191/* SACK related state */ 192 int sack_enable; /* enable SACK for this connection */ 193 int snd_numholes; /* number of holes seen by sender */ 194 TAILQ_HEAD(sackhole_head, sackhole) snd_holes; 195 /* SACK scoreboard (sorted) */ 196 tcp_seq snd_fack; /* last seq number(+1) sack'd by rcv'r*/ 197 int rcv_numsacks; /* # distinct sack blks present */ 198 struct sackblk sackblks[MAX_SACK_BLKS]; /* seq nos. of sack blocks */ 199 tcp_seq sack_newdata; /* New data xmitted in this recovery 200 episode starts at this seq number */ 201 struct sackhint sackhint; /* SACK scoreboard hint */ 202 int t_rttlow; /* smallest observerved RTT */ 203}; 204 205#define IN_FASTRECOVERY(tp) (tp->t_flags & TF_FASTRECOVERY) 206#define ENTER_FASTRECOVERY(tp) tp->t_flags |= TF_FASTRECOVERY 207#define EXIT_FASTRECOVERY(tp) tp->t_flags &= ~TF_FASTRECOVERY 208 209#ifdef TCP_SIGNATURE 210/* 211 * Defines which are needed by the xform_tcp module and tcp_[in|out]put 212 * for SADB verification and lookup. 213 */ 214#define TCP_SIGLEN 16 /* length of computed digest in bytes */ 215#define TCP_KEYLEN_MIN 1 /* minimum length of TCP-MD5 key */ 216#define TCP_KEYLEN_MAX 80 /* maximum length of TCP-MD5 key */ 217/* 218 * Only a single SA per host may be specified at this time. An SPI is 219 * needed in order for the KEY_ALLOCSA() lookup to work. 220 */ 221#define TCP_SIG_SPI 0x1000 222#endif /* TCP_SIGNATURE */ 223 224/* 225 * Structure to hold TCP options that are only used during segment 226 * processing (in tcp_input), but not held in the tcpcb. 227 * It's basically used to reduce the number of parameters 228 * to tcp_dooptions. 229 */ 230struct tcpopt { 231 u_long to_flags; /* which options are present */ 232#define TOF_TS 0x0001 /* timestamp */ 233#define TOF_MSS 0x0010 234#define TOF_SCALE 0x0020 235#define TOF_SIGNATURE 0x0040 /* signature option present */ 236#define TOF_SIGLEN 0x0080 /* signature length valid (RFC2385) */ 237#define TOF_SACK 0x0100 /* Peer sent SACK option */ 238 u_int32_t to_tsval; 239 u_int32_t to_tsecr; 240 u_int16_t to_mss; 241 u_int8_t to_requested_s_scale; 242 u_int8_t to_nsacks; /* number of SACK blocks */ 243 u_char *to_sacks; /* pointer to the first SACK blocks */ 244}; 245 246#ifdef _NETINET_IN_PCB_H_ 247struct syncache { 248 inp_gen_t sc_inp_gencnt; /* pointer check */ 249 struct tcpcb *sc_tp; /* tcb for listening socket */ 250 struct mbuf *sc_ipopts; /* source route */ 251 struct in_conninfo sc_inc; /* addresses */ 252 u_int32_t sc_tsrecent; 253 u_int32_t sc_flowlabel; /* IPv6 flowlabel */ 254 tcp_seq sc_irs; /* seq from peer */ 255 tcp_seq sc_iss; /* our ISS */ 256 u_long sc_rxttime; /* retransmit time */ 257 u_int16_t sc_rxtslot; /* retransmit counter */ 258 u_int16_t sc_peer_mss; /* peer's MSS */ 259 u_int16_t sc_wnd; /* advertised window */ 260 u_int8_t sc_requested_s_scale:4, 261 sc_request_r_scale:4; 262 u_int8_t sc_flags; 263#define SCF_NOOPT 0x01 /* no TCP options */ 264#define SCF_WINSCALE 0x02 /* negotiated window scaling */ 265#define SCF_TIMESTAMP 0x04 /* negotiated timestamps */ 266#define SCF_UNREACH 0x10 /* icmp unreachable received */ 267#define SCF_SIGNATURE 0x20 /* send MD5 digests */ 268#define SCF_SACK 0x80 /* send SACK option */ 269 TAILQ_ENTRY(syncache) sc_hash; 270 TAILQ_ENTRY(syncache) sc_timerq; 271}; 272 273struct syncache_head { 274 TAILQ_HEAD(, syncache) sch_bucket; 275 u_int sch_length; 276}; 277#else 278struct in_conninfo; 279#endif /* _NETINET_IN_PCB_H_ */ 280 281struct hc_metrics_lite { /* must stay in sync with hc_metrics */ 282 u_long rmx_mtu; /* MTU for this path */ 283 u_long rmx_ssthresh; /* outbound gateway buffer limit */ 284 u_long rmx_rtt; /* estimated round trip time */ 285 u_long rmx_rttvar; /* estimated rtt variance */ 286 u_long rmx_bandwidth; /* estimated bandwidth */ 287 u_long rmx_cwnd; /* congestion window */ 288 u_long rmx_sendpipe; /* outbound delay-bandwidth product */ 289 u_long rmx_recvpipe; /* inbound delay-bandwidth product */ 290}; 291 292struct tcptw { 293 struct inpcb *tw_inpcb; /* XXX back pointer to internet pcb */ 294 tcp_seq snd_nxt; 295 tcp_seq rcv_nxt; 296 tcp_seq iss; 297 tcp_seq irs; 298 u_short last_win; /* cached window value */ 299 u_short tw_so_options; /* copy of so_options */ 300 struct ucred *tw_cred; /* user credentials */ 301 u_long t_recent; 302 u_long t_starttime; 303 int tw_time; 304 LIST_ENTRY(tcptw) tw_2msl; 305}; 306 307#define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb) 308#define intotw(ip) ((struct tcptw *)(ip)->inp_ppcb) 309#define sototcpcb(so) (intotcpcb(sotoinpcb(so))) 310 311/* 312 * The smoothed round-trip time and estimated variance 313 * are stored as fixed point numbers scaled by the values below. 314 * For convenience, these scales are also used in smoothing the average 315 * (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed). 316 * With these scales, srtt has 3 bits to the right of the binary point, 317 * and thus an "ALPHA" of 0.875. rttvar has 2 bits to the right of the 318 * binary point, and is smoothed with an ALPHA of 0.75. 319 */ 320#define TCP_RTT_SCALE 32 /* multiplier for srtt; 3 bits frac. */ 321#define TCP_RTT_SHIFT 5 /* shift for srtt; 3 bits frac. */ 322#define TCP_RTTVAR_SCALE 16 /* multiplier for rttvar; 2 bits */ 323#define TCP_RTTVAR_SHIFT 4 /* shift for rttvar; 2 bits */ 324#define TCP_DELTA_SHIFT 2 /* see tcp_input.c */ 325 326/* 327 * The initial retransmission should happen at rtt + 4 * rttvar. 328 * Because of the way we do the smoothing, srtt and rttvar 329 * will each average +1/2 tick of bias. When we compute 330 * the retransmit timer, we want 1/2 tick of rounding and 331 * 1 extra tick because of +-1/2 tick uncertainty in the 332 * firing of the timer. The bias will give us exactly the 333 * 1.5 tick we need. But, because the bias is 334 * statistical, we have to test that we don't drop below 335 * the minimum feasible timer (which is 2 ticks). 336 * This version of the macro adapted from a paper by Lawrence 337 * Brakmo and Larry Peterson which outlines a problem caused 338 * by insufficient precision in the original implementation, 339 * which results in inappropriately large RTO values for very 340 * fast networks. 341 */ 342#define TCP_REXMTVAL(tp) \ 343 max((tp)->t_rttmin, (((tp)->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT)) \ 344 + (tp)->t_rttvar) >> TCP_DELTA_SHIFT) 345 346/* 347 * TCP statistics. 348 * Many of these should be kept per connection, 349 * but that's inconvenient at the moment. 350 */ 351struct tcpstat { 352 u_long tcps_connattempt; /* connections initiated */ 353 u_long tcps_accepts; /* connections accepted */ 354 u_long tcps_connects; /* connections established */ 355 u_long tcps_drops; /* connections dropped */ 356 u_long tcps_conndrops; /* embryonic connections dropped */ 357 u_long tcps_minmssdrops; /* average minmss too low drops */ 358 u_long tcps_closed; /* conn. closed (includes drops) */ 359 u_long tcps_segstimed; /* segs where we tried to get rtt */ 360 u_long tcps_rttupdated; /* times we succeeded */ 361 u_long tcps_delack; /* delayed acks sent */ 362 u_long tcps_timeoutdrop; /* conn. dropped in rxmt timeout */ 363 u_long tcps_rexmttimeo; /* retransmit timeouts */ 364 u_long tcps_persisttimeo; /* persist timeouts */ 365 u_long tcps_keeptimeo; /* keepalive timeouts */ 366 u_long tcps_keepprobe; /* keepalive probes sent */ 367 u_long tcps_keepdrops; /* connections dropped in keepalive */ 368 369 u_long tcps_sndtotal; /* total packets sent */ 370 u_long tcps_sndpack; /* data packets sent */ 371 u_long tcps_sndbyte; /* data bytes sent */ 372 u_long tcps_sndrexmitpack; /* data packets retransmitted */ 373 u_long tcps_sndrexmitbyte; /* data bytes retransmitted */ 374 u_long tcps_sndrexmitbad; /* unnecessary packet retransmissions */ 375 u_long tcps_sndacks; /* ack-only packets sent */ 376 u_long tcps_sndprobe; /* window probes sent */ 377 u_long tcps_sndurg; /* packets sent with URG only */ 378 u_long tcps_sndwinup; /* window update-only packets sent */ 379 u_long tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */ 380 381 u_long tcps_rcvtotal; /* total packets received */ 382 u_long tcps_rcvpack; /* packets received in sequence */ 383 u_long tcps_rcvbyte; /* bytes received in sequence */ 384 u_long tcps_rcvbadsum; /* packets received with ccksum errs */ 385 u_long tcps_rcvbadoff; /* packets received with bad offset */ 386 u_long tcps_rcvmemdrop; /* packets dropped for lack of memory */ 387 u_long tcps_rcvshort; /* packets received too short */ 388 u_long tcps_rcvduppack; /* duplicate-only packets received */ 389 u_long tcps_rcvdupbyte; /* duplicate-only bytes received */ 390 u_long tcps_rcvpartduppack; /* packets with some duplicate data */ 391 u_long tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */ 392 u_long tcps_rcvoopack; /* out-of-order packets received */ 393 u_long tcps_rcvoobyte; /* out-of-order bytes received */ 394 u_long tcps_rcvpackafterwin; /* packets with data after window */ 395 u_long tcps_rcvbyteafterwin; /* bytes rcvd after window */ 396 u_long tcps_rcvafterclose; /* packets rcvd after "close" */ 397 u_long tcps_rcvwinprobe; /* rcvd window probe packets */ 398 u_long tcps_rcvdupack; /* rcvd duplicate acks */ 399 u_long tcps_rcvacktoomuch; /* rcvd acks for unsent data */ 400 u_long tcps_rcvackpack; /* rcvd ack packets */ 401 u_long tcps_rcvackbyte; /* bytes acked by rcvd acks */ 402 u_long tcps_rcvwinupd; /* rcvd window update packets */ 403 u_long tcps_pawsdrop; /* segments dropped due to PAWS */ 404 u_long tcps_predack; /* times hdr predict ok for acks */ 405 u_long tcps_preddat; /* times hdr predict ok for data pkts */ 406 u_long tcps_pcbcachemiss; 407 u_long tcps_cachedrtt; /* times cached RTT in route updated */ 408 u_long tcps_cachedrttvar; /* times cached rttvar updated */ 409 u_long tcps_cachedssthresh; /* times cached ssthresh updated */ 410 u_long tcps_usedrtt; /* times RTT initialized from route */ 411 u_long tcps_usedrttvar; /* times RTTVAR initialized from rt */ 412 u_long tcps_usedssthresh; /* times ssthresh initialized from rt*/ 413 u_long tcps_persistdrop; /* timeout in persist state */ 414 u_long tcps_badsyn; /* bogus SYN, e.g. premature ACK */ 415 u_long tcps_mturesent; /* resends due to MTU discovery */ 416 u_long tcps_listendrop; /* listen queue overflows */ 417 u_long tcps_badrst; /* ignored RSTs in the window */ 418 419 u_long tcps_sc_added; /* entry added to syncache */ 420 u_long tcps_sc_retransmitted; /* syncache entry was retransmitted */ 421 u_long tcps_sc_dupsyn; /* duplicate SYN packet */ 422 u_long tcps_sc_dropped; /* could not reply to packet */ 423 u_long tcps_sc_completed; /* successful extraction of entry */ 424 u_long tcps_sc_bucketoverflow; /* syncache per-bucket limit hit */ 425 u_long tcps_sc_cacheoverflow; /* syncache cache limit hit */ 426 u_long tcps_sc_reset; /* RST removed entry from syncache */ 427 u_long tcps_sc_stale; /* timed out or listen socket gone */ 428 u_long tcps_sc_aborted; /* syncache entry aborted */ 429 u_long tcps_sc_badack; /* removed due to bad ACK */ 430 u_long tcps_sc_unreach; /* ICMP unreachable received */ 431 u_long tcps_sc_zonefail; /* zalloc() failed */ 432 u_long tcps_sc_sendcookie; /* SYN cookie sent */ 433 u_long tcps_sc_recvcookie; /* SYN cookie received */ 434 435 u_long tcps_hc_added; /* entry added to hostcache */ 436 u_long tcps_hc_bucketoverflow; /* hostcache per bucket limit hit */ 437 438 /* SACK related stats */ 439 u_long tcps_sack_recovery_episode; /* SACK recovery episodes */ 440 u_long tcps_sack_rexmits; /* SACK rexmit segments */ 441 u_long tcps_sack_rexmit_bytes; /* SACK rexmit bytes */ 442 u_long tcps_sack_rcv_blocks; /* SACK blocks (options) received */ 443 u_long tcps_sack_send_blocks; /* SACK blocks (options) sent */ 444 u_long tcps_sack_sboverflow; /* times scoreboard overflowed */ 445}; 446 447/* 448 * TCB structure exported to user-land via sysctl(3). 449 * Evil hack: declare only if in_pcb.h and sys/socketvar.h have been 450 * included. Not all of our clients do. 451 */ 452#if defined(_NETINET_IN_PCB_H_) && defined(_SYS_SOCKETVAR_H_) 453struct xtcpcb { 454 size_t xt_len; 455 struct inpcb xt_inp; 456 struct tcpcb xt_tp; 457 struct xsocket xt_socket; 458 u_quad_t xt_alignment_hack; 459}; 460#endif 461 462/* 463 * Names for TCP sysctl objects 464 */ 465#define TCPCTL_DO_RFC1323 1 /* use RFC-1323 extensions */ 466#define TCPCTL_MSSDFLT 3 /* MSS default */ 467#define TCPCTL_STATS 4 /* statistics (read-only) */ 468#define TCPCTL_RTTDFLT 5 /* default RTT estimate */ 469#define TCPCTL_KEEPIDLE 6 /* keepalive idle timer */ 470#define TCPCTL_KEEPINTVL 7 /* interval to send keepalives */ 471#define TCPCTL_SENDSPACE 8 /* send buffer space */ 472#define TCPCTL_RECVSPACE 9 /* receive buffer space */ 473#define TCPCTL_KEEPINIT 10 /* timeout for establishing syn */ 474#define TCPCTL_PCBLIST 11 /* list of all outstanding PCBs */ 475#define TCPCTL_DELACKTIME 12 /* time before sending delayed ACK */ 476#define TCPCTL_V6MSSDFLT 13 /* MSS default for IPv6 */ 477#define TCPCTL_SACK 14 /* Selective Acknowledgement,rfc 2018 */ 478#define TCPCTL_DROP 15 /* drop tcp connection */ 479#define TCPCTL_MAXID 16 480 481#define TCPCTL_NAMES { \ 482 { 0, 0 }, \ 483 { "rfc1323", CTLTYPE_INT }, \ 484 { "mssdflt", CTLTYPE_INT }, \ 485 { "stats", CTLTYPE_STRUCT }, \ 486 { "rttdflt", CTLTYPE_INT }, \ 487 { "keepidle", CTLTYPE_INT }, \ 488 { "keepintvl", CTLTYPE_INT }, \ 489 { "sendspace", CTLTYPE_INT }, \ 490 { "recvspace", CTLTYPE_INT }, \ 491 { "keepinit", CTLTYPE_INT }, \ 492 { "pcblist", CTLTYPE_STRUCT }, \ 493 { "delacktime", CTLTYPE_INT }, \ 494 { "v6mssdflt", CTLTYPE_INT }, \ 495 { "maxid", CTLTYPE_INT }, \ 496} 497 498 499#ifdef _KERNEL 500#ifdef SYSCTL_DECL 501SYSCTL_DECL(_net_inet_tcp); 502SYSCTL_DECL(_net_inet_tcp_sack); 503#endif 504 505extern struct inpcbhead tcb; /* head of queue of active tcpcb's */ 506extern struct inpcbinfo tcbinfo; 507extern struct tcpstat tcpstat; /* tcp statistics */ 508extern int tcp_mssdflt; /* XXX */ 509extern int tcp_minmss; 510extern int tcp_minmssoverload; 511extern int tcp_delack_enabled; 512extern int tcp_do_newreno; 513extern int path_mtu_discovery; 514extern int ss_fltsz; 515extern int ss_fltsz_local; 516 517extern int tcp_do_sack; /* SACK enabled/disabled */ 518 519struct tcpcb * 520 tcp_close(struct tcpcb *); 521void tcp_discardcb(struct tcpcb *); 522void tcp_twstart(struct tcpcb *); 523int tcp_twrecycleable(struct tcptw *tw); 524void tcp_twclose(struct tcptw *_tw, int _reuse); 525void tcp_ctlinput(int, struct sockaddr *, void *); 526int tcp_ctloutput(struct socket *, struct sockopt *); 527struct tcpcb * 528 tcp_drop(struct tcpcb *, int); 529void tcp_drain(void); 530void tcp_fasttimo(void); 531void tcp_init(void); 532void tcp_fini(void *); 533void tcp_reass_init(void); 534void tcp_input(struct mbuf *, int); 535u_long tcp_maxmtu(struct in_conninfo *); 536u_long tcp_maxmtu6(struct in_conninfo *); 537void tcp_mss(struct tcpcb *, int); 538int tcp_mssopt(struct in_conninfo *); 539struct inpcb * 540 tcp_drop_syn_sent(struct inpcb *, int); 541struct inpcb * 542 tcp_mtudisc(struct inpcb *, int); 543struct tcpcb * 544 tcp_newtcpcb(struct inpcb *); 545int tcp_output(struct tcpcb *); 546void tcp_respond(struct tcpcb *, void *, 547 struct tcphdr *, struct mbuf *, tcp_seq, tcp_seq, int); 548int tcp_twrespond(struct tcptw *, int); 549void tcp_setpersist(struct tcpcb *); 550#ifdef TCP_SIGNATURE 551int tcp_signature_compute(struct mbuf *, int, int, int, u_char *, u_int); 552#endif 553void tcp_slowtimo(void); 554struct tcptemp * 555 tcpip_maketemplate(struct inpcb *); 556void tcpip_fillheaders(struct inpcb *, void *, void *); 557struct tcpcb * 558 tcp_timers(struct tcpcb *, int); 559void tcp_trace(int, int, struct tcpcb *, void *, struct tcphdr *, int); 560void tcp_xmit_bandwidth_limit(struct tcpcb *tp, tcp_seq ack_seq); 561void syncache_init(void); 562void syncache_unreach(struct in_conninfo *, struct tcphdr *); 563int syncache_expand(struct in_conninfo *, struct tcphdr *, 564 struct socket **, struct mbuf *); 565int syncache_add(struct in_conninfo *, struct tcpopt *, 566 struct tcphdr *, struct socket **, struct mbuf *); 567void syncache_chkrst(struct in_conninfo *, struct tcphdr *); 568void syncache_badack(struct in_conninfo *); 569/* 570 * All tcp_hc_* functions are IPv4 and IPv6 (via in_conninfo) 571 */ 572void tcp_hc_init(void); 573void tcp_hc_get(struct in_conninfo *, struct hc_metrics_lite *); 574u_long tcp_hc_getmtu(struct in_conninfo *); 575void tcp_hc_updatemtu(struct in_conninfo *, u_long); 576void tcp_hc_update(struct in_conninfo *, struct hc_metrics_lite *); 577 578extern struct pr_usrreqs tcp_usrreqs; 579extern u_long tcp_sendspace; 580extern u_long tcp_recvspace; 581tcp_seq tcp_new_isn(struct tcpcb *); 582 583void tcp_sack_doack(struct tcpcb *, struct tcpopt *, tcp_seq); 584void tcp_update_sack_list(struct tcpcb *tp, tcp_seq rcv_laststart, tcp_seq rcv_lastend); 585void tcp_clean_sackreport(struct tcpcb *tp); 586void tcp_sack_adjust(struct tcpcb *tp); 587struct sackhole *tcp_sack_output(struct tcpcb *tp, int *sack_bytes_rexmt); 588void tcp_sack_partialack(struct tcpcb *, struct tcphdr *); 589void tcp_free_sackholes(struct tcpcb *tp); 590int tcp_newreno(struct tcpcb *, struct tcphdr *); 591u_long tcp_seq_subtract(u_long, u_long ); 592 593#endif /* _KERNEL */ 594 595#endif /* _NETINET_TCP_VAR_H_ */ 596