tcp_var.h revision 145370
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 145370 2005-04-21 20:11:01Z ps $ 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 tcptemp { 67 u_char tt_ipgen[40]; /* the size must be of max ip header, now IPv6 */ 68 struct tcphdr tt_t; 69}; 70 71#define tcp6cb tcpcb /* for KAME src sync over BSD*'s */ 72 73/* 74 * Tcp control block, one per tcp; fields: 75 * Organized for 16 byte cacheline efficiency. 76 */ 77struct tcpcb { 78 struct tsegqe_head t_segq; /* segment reassembly queue */ 79 int t_segqlen; /* segment reassembly queue length */ 80 int t_dupacks; /* consecutive dup acks recd */ 81 82 struct callout *tt_rexmt; /* retransmit timer */ 83 struct callout *tt_persist; /* retransmit persistence */ 84 struct callout *tt_keep; /* keepalive */ 85 struct callout *tt_2msl; /* 2*msl TIME_WAIT timer */ 86 struct callout *tt_delack; /* delayed ACK timer */ 87 88 struct inpcb *t_inpcb; /* back pointer to internet pcb */ 89 int t_state; /* state of this connection */ 90 u_int t_flags; 91#define TF_ACKNOW 0x000001 /* ack peer immediately */ 92#define TF_DELACK 0x000002 /* ack, but try to delay it */ 93#define TF_NODELAY 0x000004 /* don't delay packets to coalesce */ 94#define TF_NOOPT 0x000008 /* don't use tcp options */ 95#define TF_SENTFIN 0x000010 /* have sent FIN */ 96#define TF_REQ_SCALE 0x000020 /* have/will request window scaling */ 97#define TF_RCVD_SCALE 0x000040 /* other side has requested scaling */ 98#define TF_REQ_TSTMP 0x000080 /* have/will request timestamps */ 99#define TF_RCVD_TSTMP 0x000100 /* a timestamp was received in SYN */ 100#define TF_SACK_PERMIT 0x000200 /* other side said I could SACK */ 101#define TF_NEEDSYN 0x000400 /* send SYN (implicit state) */ 102#define TF_NEEDFIN 0x000800 /* send FIN (implicit state) */ 103#define TF_NOPUSH 0x001000 /* don't push */ 104#define TF_MORETOCOME 0x010000 /* More data to be appended to sock */ 105#define TF_LQ_OVERFLOW 0x020000 /* listen queue overflow */ 106#define TF_LASTIDLE 0x040000 /* connection was previously idle */ 107#define TF_RXWIN0SENT 0x080000 /* sent a receiver win 0 in response */ 108#define TF_FASTRECOVERY 0x100000 /* in NewReno Fast Recovery */ 109#define TF_WASFRECOVERY 0x200000 /* was in NewReno Fast Recovery */ 110#define TF_SIGNATURE 0x400000 /* require MD5 digests (RFC2385) */ 111 int t_force; /* 1 if forcing out a byte */ 112 113 tcp_seq snd_una; /* send unacknowledged */ 114 tcp_seq snd_max; /* highest sequence number sent; 115 * used to recognize retransmits 116 */ 117 tcp_seq snd_nxt; /* send next */ 118 tcp_seq snd_up; /* send urgent pointer */ 119 120 tcp_seq snd_wl1; /* window update seg seq number */ 121 tcp_seq snd_wl2; /* window update seg ack number */ 122 tcp_seq iss; /* initial send sequence number */ 123 tcp_seq irs; /* initial receive sequence number */ 124 125 tcp_seq rcv_nxt; /* receive next */ 126 tcp_seq rcv_adv; /* advertised window */ 127 u_long rcv_wnd; /* receive window */ 128 tcp_seq rcv_up; /* receive urgent pointer */ 129 130 u_long snd_wnd; /* send window */ 131 u_long snd_cwnd; /* congestion-controlled window */ 132 u_long snd_bwnd; /* bandwidth-controlled window */ 133 u_long snd_ssthresh; /* snd_cwnd size threshold for 134 * for slow start exponential to 135 * linear switch 136 */ 137 u_long snd_bandwidth; /* calculated bandwidth or 0 */ 138 tcp_seq snd_recover; /* for use in NewReno Fast Recovery */ 139 140 u_int t_maxopd; /* mss plus options */ 141 142 u_long t_rcvtime; /* inactivity time */ 143 u_long t_starttime; /* time connection was established */ 144 int t_rtttime; /* round trip time */ 145 tcp_seq t_rtseq; /* sequence number being timed */ 146 147 int t_bw_rtttime; /* used for bandwidth calculation */ 148 tcp_seq t_bw_rtseq; /* used for bandwidth calculation */ 149 150 int t_rxtcur; /* current retransmit value (ticks) */ 151 u_int t_maxseg; /* maximum segment size */ 152 int t_srtt; /* smoothed round-trip time */ 153 int t_rttvar; /* variance in round-trip time */ 154 155 int t_rxtshift; /* log(2) of rexmt exp. backoff */ 156 u_int t_rttmin; /* minimum rtt allowed */ 157 u_int t_rttbest; /* best rtt we've seen */ 158 u_long t_rttupdated; /* number of times rtt sampled */ 159 u_long max_sndwnd; /* largest window peer has offered */ 160 161 int t_softerror; /* possible error not yet reported */ 162/* out-of-band data */ 163 char t_oobflags; /* have some */ 164 char t_iobc; /* input character */ 165#define TCPOOB_HAVEDATA 0x01 166#define TCPOOB_HADDATA 0x02 167/* RFC 1323 variables */ 168 u_char snd_scale; /* window scaling for send window */ 169 u_char rcv_scale; /* window scaling for recv window */ 170 u_char request_r_scale; /* pending window scaling */ 171 u_char requested_s_scale; 172 u_long ts_recent; /* timestamp echo data */ 173 174 u_long ts_recent_age; /* when last updated */ 175 tcp_seq last_ack_sent; 176/* experimental */ 177 u_long snd_cwnd_prev; /* cwnd prior to retransmit */ 178 u_long snd_ssthresh_prev; /* ssthresh prior to retransmit */ 179 tcp_seq snd_recover_prev; /* snd_recover prior to retransmit */ 180 u_long t_badrxtwin; /* window for retransmit recovery */ 181 u_char snd_limited; /* segments limited transmitted */ 182/* anti DoS counters */ 183 u_long rcv_second; /* start of interval second */ 184 u_long rcv_pps; /* received packets per second */ 185 u_long rcv_byps; /* received bytes per second */ 186/* SACK related state */ 187 int sack_enable; /* enable SACK for this connection */ 188 int snd_numholes; /* number of holes seen by sender */ 189 TAILQ_HEAD(, sackhole) snd_holes; /* SACK scoreboard (sorted) */ 190 tcp_seq rcv_lastsack; /* last seq number(+1) sack'd by rcv'r*/ 191 int rcv_numsacks; /* # distinct sack blks present */ 192 struct sackblk sackblks[MAX_SACK_BLKS]; /* seq nos. of sack blocks */ 193 tcp_seq sack_newdata; /* New data xmitted in this recovery 194 episode starts at this seq number */ 195}; 196 197#define IN_FASTRECOVERY(tp) (tp->t_flags & TF_FASTRECOVERY) 198#define ENTER_FASTRECOVERY(tp) tp->t_flags |= TF_FASTRECOVERY 199#define EXIT_FASTRECOVERY(tp) tp->t_flags &= ~TF_FASTRECOVERY 200 201#ifdef TCP_SIGNATURE 202/* 203 * Defines which are needed by the xform_tcp module and tcp_[in|out]put 204 * for SADB verification and lookup. 205 */ 206#define TCP_SIGLEN 16 /* length of computed digest in bytes */ 207#define TCP_KEYLEN_MIN 1 /* minimum length of TCP-MD5 key */ 208#define TCP_KEYLEN_MAX 80 /* maximum length of TCP-MD5 key */ 209/* 210 * Only a single SA per host may be specified at this time. An SPI is 211 * needed in order for the KEY_ALLOCSA() lookup to work. 212 */ 213#define TCP_SIG_SPI 0x1000 214#endif /* TCP_SIGNATURE */ 215 216/* 217 * Structure to hold TCP options that are only used during segment 218 * processing (in tcp_input), but not held in the tcpcb. 219 * It's basically used to reduce the number of parameters 220 * to tcp_dooptions. 221 */ 222struct tcpopt { 223 u_long to_flags; /* which options are present */ 224#define TOF_TS 0x0001 /* timestamp */ 225#define TOF_MSS 0x0010 226#define TOF_SCALE 0x0020 227#define TOF_SIGNATURE 0x0040 /* signature option present */ 228#define TOF_SIGLEN 0x0080 /* signature length valid (RFC2385) */ 229#define TOF_SACK 0x0100 /* Peer sent SACK option */ 230 u_int32_t to_tsval; 231 u_int32_t to_tsecr; 232 u_int16_t to_mss; 233 u_int8_t to_requested_s_scale; 234 u_int8_t to_pad; 235}; 236 237#ifdef _NETINET_IN_PCB_H_ 238struct syncache { 239 inp_gen_t sc_inp_gencnt; /* pointer check */ 240 struct tcpcb *sc_tp; /* tcb for listening socket */ 241 struct mbuf *sc_ipopts; /* source route */ 242 struct in_conninfo sc_inc; /* addresses */ 243 u_int32_t sc_tsrecent; 244 u_int32_t sc_flowlabel; /* IPv6 flowlabel */ 245 tcp_seq sc_irs; /* seq from peer */ 246 tcp_seq sc_iss; /* our ISS */ 247 u_long sc_rxttime; /* retransmit time */ 248 u_int16_t sc_rxtslot; /* retransmit counter */ 249 u_int16_t sc_peer_mss; /* peer's MSS */ 250 u_int16_t sc_wnd; /* advertised window */ 251 u_int8_t sc_requested_s_scale:4, 252 sc_request_r_scale:4; 253 u_int8_t sc_flags; 254#define SCF_NOOPT 0x01 /* no TCP options */ 255#define SCF_WINSCALE 0x02 /* negotiated window scaling */ 256#define SCF_TIMESTAMP 0x04 /* negotiated timestamps */ 257#define SCF_UNREACH 0x10 /* icmp unreachable received */ 258#define SCF_SIGNATURE 0x20 /* send MD5 digests */ 259#define SCF_SACK 0x80 /* send SACK option */ 260 TAILQ_ENTRY(syncache) sc_hash; 261 TAILQ_ENTRY(syncache) sc_timerq; 262}; 263 264struct syncache_head { 265 TAILQ_HEAD(, syncache) sch_bucket; 266 u_int sch_length; 267}; 268#else 269struct in_conninfo; 270#endif /* _NETINET_IN_PCB_H_ */ 271 272struct hc_metrics_lite { /* must stay in sync with hc_metrics */ 273 u_long rmx_mtu; /* MTU for this path */ 274 u_long rmx_ssthresh; /* outbound gateway buffer limit */ 275 u_long rmx_rtt; /* estimated round trip time */ 276 u_long rmx_rttvar; /* estimated rtt variance */ 277 u_long rmx_bandwidth; /* estimated bandwidth */ 278 u_long rmx_cwnd; /* congestion window */ 279 u_long rmx_sendpipe; /* outbound delay-bandwidth product */ 280 u_long rmx_recvpipe; /* inbound delay-bandwidth product */ 281}; 282 283struct tcptw { 284 struct inpcb *tw_inpcb; /* XXX back pointer to internet pcb */ 285 tcp_seq snd_nxt; 286 tcp_seq rcv_nxt; 287 tcp_seq iss; 288 tcp_seq irs; 289 u_short last_win; /* cached window value */ 290 u_short tw_so_options; /* copy of so_options */ 291 struct ucred *tw_cred; /* user credentials */ 292 u_long t_recent; 293 u_long t_starttime; 294 int tw_time; 295 LIST_ENTRY(tcptw) tw_2msl; 296}; 297 298#define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb) 299#define intotw(ip) ((struct tcptw *)(ip)->inp_ppcb) 300#define sototcpcb(so) (intotcpcb(sotoinpcb(so))) 301 302/* 303 * The smoothed round-trip time and estimated variance 304 * are stored as fixed point numbers scaled by the values below. 305 * For convenience, these scales are also used in smoothing the average 306 * (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed). 307 * With these scales, srtt has 3 bits to the right of the binary point, 308 * and thus an "ALPHA" of 0.875. rttvar has 2 bits to the right of the 309 * binary point, and is smoothed with an ALPHA of 0.75. 310 */ 311#define TCP_RTT_SCALE 32 /* multiplier for srtt; 3 bits frac. */ 312#define TCP_RTT_SHIFT 5 /* shift for srtt; 3 bits frac. */ 313#define TCP_RTTVAR_SCALE 16 /* multiplier for rttvar; 2 bits */ 314#define TCP_RTTVAR_SHIFT 4 /* shift for rttvar; 2 bits */ 315#define TCP_DELTA_SHIFT 2 /* see tcp_input.c */ 316 317/* 318 * The initial retransmission should happen at rtt + 4 * rttvar. 319 * Because of the way we do the smoothing, srtt and rttvar 320 * will each average +1/2 tick of bias. When we compute 321 * the retransmit timer, we want 1/2 tick of rounding and 322 * 1 extra tick because of +-1/2 tick uncertainty in the 323 * firing of the timer. The bias will give us exactly the 324 * 1.5 tick we need. But, because the bias is 325 * statistical, we have to test that we don't drop below 326 * the minimum feasible timer (which is 2 ticks). 327 * This version of the macro adapted from a paper by Lawrence 328 * Brakmo and Larry Peterson which outlines a problem caused 329 * by insufficient precision in the original implementation, 330 * which results in inappropriately large RTO values for very 331 * fast networks. 332 */ 333#define TCP_REXMTVAL(tp) \ 334 max((tp)->t_rttmin, (((tp)->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT)) \ 335 + (tp)->t_rttvar) >> TCP_DELTA_SHIFT) 336 337/* 338 * TCP statistics. 339 * Many of these should be kept per connection, 340 * but that's inconvenient at the moment. 341 */ 342struct tcpstat { 343 u_long tcps_connattempt; /* connections initiated */ 344 u_long tcps_accepts; /* connections accepted */ 345 u_long tcps_connects; /* connections established */ 346 u_long tcps_drops; /* connections dropped */ 347 u_long tcps_conndrops; /* embryonic connections dropped */ 348 u_long tcps_minmssdrops; /* average minmss too low drops */ 349 u_long tcps_closed; /* conn. closed (includes drops) */ 350 u_long tcps_segstimed; /* segs where we tried to get rtt */ 351 u_long tcps_rttupdated; /* times we succeeded */ 352 u_long tcps_delack; /* delayed acks sent */ 353 u_long tcps_timeoutdrop; /* conn. dropped in rxmt timeout */ 354 u_long tcps_rexmttimeo; /* retransmit timeouts */ 355 u_long tcps_persisttimeo; /* persist timeouts */ 356 u_long tcps_keeptimeo; /* keepalive timeouts */ 357 u_long tcps_keepprobe; /* keepalive probes sent */ 358 u_long tcps_keepdrops; /* connections dropped in keepalive */ 359 360 u_long tcps_sndtotal; /* total packets sent */ 361 u_long tcps_sndpack; /* data packets sent */ 362 u_long tcps_sndbyte; /* data bytes sent */ 363 u_long tcps_sndrexmitpack; /* data packets retransmitted */ 364 u_long tcps_sndrexmitbyte; /* data bytes retransmitted */ 365 u_long tcps_sndrexmitbad; /* unnecessary packet retransmissions */ 366 u_long tcps_sndacks; /* ack-only packets sent */ 367 u_long tcps_sndprobe; /* window probes sent */ 368 u_long tcps_sndurg; /* packets sent with URG only */ 369 u_long tcps_sndwinup; /* window update-only packets sent */ 370 u_long tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */ 371 372 u_long tcps_rcvtotal; /* total packets received */ 373 u_long tcps_rcvpack; /* packets received in sequence */ 374 u_long tcps_rcvbyte; /* bytes received in sequence */ 375 u_long tcps_rcvbadsum; /* packets received with ccksum errs */ 376 u_long tcps_rcvbadoff; /* packets received with bad offset */ 377 u_long tcps_rcvmemdrop; /* packets dropped for lack of memory */ 378 u_long tcps_rcvshort; /* packets received too short */ 379 u_long tcps_rcvduppack; /* duplicate-only packets received */ 380 u_long tcps_rcvdupbyte; /* duplicate-only bytes received */ 381 u_long tcps_rcvpartduppack; /* packets with some duplicate data */ 382 u_long tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */ 383 u_long tcps_rcvoopack; /* out-of-order packets received */ 384 u_long tcps_rcvoobyte; /* out-of-order bytes received */ 385 u_long tcps_rcvpackafterwin; /* packets with data after window */ 386 u_long tcps_rcvbyteafterwin; /* bytes rcvd after window */ 387 u_long tcps_rcvafterclose; /* packets rcvd after "close" */ 388 u_long tcps_rcvwinprobe; /* rcvd window probe packets */ 389 u_long tcps_rcvdupack; /* rcvd duplicate acks */ 390 u_long tcps_rcvacktoomuch; /* rcvd acks for unsent data */ 391 u_long tcps_rcvackpack; /* rcvd ack packets */ 392 u_long tcps_rcvackbyte; /* bytes acked by rcvd acks */ 393 u_long tcps_rcvwinupd; /* rcvd window update packets */ 394 u_long tcps_pawsdrop; /* segments dropped due to PAWS */ 395 u_long tcps_predack; /* times hdr predict ok for acks */ 396 u_long tcps_preddat; /* times hdr predict ok for data pkts */ 397 u_long tcps_pcbcachemiss; 398 u_long tcps_cachedrtt; /* times cached RTT in route updated */ 399 u_long tcps_cachedrttvar; /* times cached rttvar updated */ 400 u_long tcps_cachedssthresh; /* times cached ssthresh updated */ 401 u_long tcps_usedrtt; /* times RTT initialized from route */ 402 u_long tcps_usedrttvar; /* times RTTVAR initialized from rt */ 403 u_long tcps_usedssthresh; /* times ssthresh initialized from rt*/ 404 u_long tcps_persistdrop; /* timeout in persist state */ 405 u_long tcps_badsyn; /* bogus SYN, e.g. premature ACK */ 406 u_long tcps_mturesent; /* resends due to MTU discovery */ 407 u_long tcps_listendrop; /* listen queue overflows */ 408 u_long tcps_badrst; /* ignored RSTs in the window */ 409 410 u_long tcps_sc_added; /* entry added to syncache */ 411 u_long tcps_sc_retransmitted; /* syncache entry was retransmitted */ 412 u_long tcps_sc_dupsyn; /* duplicate SYN packet */ 413 u_long tcps_sc_dropped; /* could not reply to packet */ 414 u_long tcps_sc_completed; /* successful extraction of entry */ 415 u_long tcps_sc_bucketoverflow; /* syncache per-bucket limit hit */ 416 u_long tcps_sc_cacheoverflow; /* syncache cache limit hit */ 417 u_long tcps_sc_reset; /* RST removed entry from syncache */ 418 u_long tcps_sc_stale; /* timed out or listen socket gone */ 419 u_long tcps_sc_aborted; /* syncache entry aborted */ 420 u_long tcps_sc_badack; /* removed due to bad ACK */ 421 u_long tcps_sc_unreach; /* ICMP unreachable received */ 422 u_long tcps_sc_zonefail; /* zalloc() failed */ 423 u_long tcps_sc_sendcookie; /* SYN cookie sent */ 424 u_long tcps_sc_recvcookie; /* SYN cookie received */ 425 426 u_long tcps_hc_added; /* entry added to hostcache */ 427 u_long tcps_hc_bucketoverflow; /* hostcache per bucket limit hit */ 428 429 /* SACK related stats */ 430 u_long tcps_sack_recovery_episode; /* SACK recovery episodes */ 431 u_long tcps_sack_rexmits; /* SACK rexmit segments */ 432 u_long tcps_sack_rexmit_bytes; /* SACK rexmit bytes */ 433 u_long tcps_sack_rcv_blocks; /* SACK blocks (options) received */ 434 u_long tcps_sack_send_blocks; /* SACK blocks (options) sent */ 435 u_long tcps_sack_sboverflow; /* times scoreboard overflowed */ 436}; 437 438/* 439 * TCB structure exported to user-land via sysctl(3). 440 * Evil hack: declare only if in_pcb.h and sys/socketvar.h have been 441 * included. Not all of our clients do. 442 */ 443#if defined(_NETINET_IN_PCB_H_) && defined(_SYS_SOCKETVAR_H_) 444struct xtcpcb { 445 size_t xt_len; 446 struct inpcb xt_inp; 447 struct tcpcb xt_tp; 448 struct xsocket xt_socket; 449 u_quad_t xt_alignment_hack; 450}; 451#endif 452 453/* 454 * Names for TCP sysctl objects 455 */ 456#define TCPCTL_DO_RFC1323 1 /* use RFC-1323 extensions */ 457#define TCPCTL_MSSDFLT 3 /* MSS default */ 458#define TCPCTL_STATS 4 /* statistics (read-only) */ 459#define TCPCTL_RTTDFLT 5 /* default RTT estimate */ 460#define TCPCTL_KEEPIDLE 6 /* keepalive idle timer */ 461#define TCPCTL_KEEPINTVL 7 /* interval to send keepalives */ 462#define TCPCTL_SENDSPACE 8 /* send buffer space */ 463#define TCPCTL_RECVSPACE 9 /* receive buffer space */ 464#define TCPCTL_KEEPINIT 10 /* timeout for establishing syn */ 465#define TCPCTL_PCBLIST 11 /* list of all outstanding PCBs */ 466#define TCPCTL_DELACKTIME 12 /* time before sending delayed ACK */ 467#define TCPCTL_V6MSSDFLT 13 /* MSS default for IPv6 */ 468#define TCPCTL_SACK 14 /* Selective Acknowledgement,rfc 2018 */ 469#define TCPCTL_DROP 15 /* drop tcp connection */ 470#define TCPCTL_MAXID 16 471 472#define TCPCTL_NAMES { \ 473 { 0, 0 }, \ 474 { "rfc1323", CTLTYPE_INT }, \ 475 { "mssdflt", CTLTYPE_INT }, \ 476 { "stats", CTLTYPE_STRUCT }, \ 477 { "rttdflt", CTLTYPE_INT }, \ 478 { "keepidle", CTLTYPE_INT }, \ 479 { "keepintvl", CTLTYPE_INT }, \ 480 { "sendspace", CTLTYPE_INT }, \ 481 { "recvspace", CTLTYPE_INT }, \ 482 { "keepinit", CTLTYPE_INT }, \ 483 { "pcblist", CTLTYPE_STRUCT }, \ 484 { "delacktime", CTLTYPE_INT }, \ 485 { "v6mssdflt", CTLTYPE_INT }, \ 486 { "maxid", CTLTYPE_INT }, \ 487} 488 489 490#ifdef _KERNEL 491#ifdef SYSCTL_DECL 492SYSCTL_DECL(_net_inet_tcp); 493SYSCTL_DECL(_net_inet_tcp_sack); 494#endif 495 496extern struct inpcbhead tcb; /* head of queue of active tcpcb's */ 497extern struct inpcbinfo tcbinfo; 498extern struct tcpstat tcpstat; /* tcp statistics */ 499extern int tcp_mssdflt; /* XXX */ 500extern int tcp_minmss; 501extern int tcp_minmssoverload; 502extern int tcp_delack_enabled; 503extern int tcp_do_newreno; 504extern int path_mtu_discovery; 505extern int ss_fltsz; 506extern int ss_fltsz_local; 507 508extern int tcp_do_sack; /* SACK enabled/disabled */ 509 510struct tcpcb * 511 tcp_close(struct tcpcb *); 512void tcp_twstart(struct tcpcb *); 513int tcp_twrecycleable(struct tcptw *tw); 514struct tcptw * 515 tcp_twclose(struct tcptw *_tw, int _reuse); 516void tcp_ctlinput(int, struct sockaddr *, void *); 517int tcp_ctloutput(struct socket *, struct sockopt *); 518struct tcpcb * 519 tcp_drop(struct tcpcb *, int); 520void tcp_drain(void); 521void tcp_fasttimo(void); 522void tcp_init(void); 523void tcp_fini(void *); 524void tcp_reass_init(void); 525void tcp_input(struct mbuf *, int); 526u_long tcp_maxmtu(struct in_conninfo *); 527u_long tcp_maxmtu6(struct in_conninfo *); 528void tcp_mss(struct tcpcb *, int); 529int tcp_mssopt(struct in_conninfo *); 530struct inpcb * 531 tcp_drop_syn_sent(struct inpcb *, int); 532struct inpcb * 533 tcp_mtudisc(struct inpcb *, int); 534struct tcpcb * 535 tcp_newtcpcb(struct inpcb *); 536int tcp_output(struct tcpcb *); 537void tcp_respond(struct tcpcb *, void *, 538 struct tcphdr *, struct mbuf *, tcp_seq, tcp_seq, int); 539int tcp_twrespond(struct tcptw *, int); 540void tcp_setpersist(struct tcpcb *); 541#ifdef TCP_SIGNATURE 542int tcp_signature_compute(struct mbuf *, int, int, int, u_char *, u_int); 543#endif 544void tcp_slowtimo(void); 545struct tcptemp * 546 tcpip_maketemplate(struct inpcb *); 547void tcpip_fillheaders(struct inpcb *, void *, void *); 548struct tcpcb * 549 tcp_timers(struct tcpcb *, int); 550void tcp_trace(int, int, struct tcpcb *, void *, struct tcphdr *, int); 551void tcp_xmit_bandwidth_limit(struct tcpcb *tp, tcp_seq ack_seq); 552void syncache_init(void); 553void syncache_unreach(struct in_conninfo *, struct tcphdr *); 554int syncache_expand(struct in_conninfo *, struct tcphdr *, 555 struct socket **, struct mbuf *); 556int syncache_add(struct in_conninfo *, struct tcpopt *, 557 struct tcphdr *, struct socket **, struct mbuf *); 558void syncache_chkrst(struct in_conninfo *, struct tcphdr *); 559void syncache_badack(struct in_conninfo *); 560/* 561 * All tcp_hc_* functions are IPv4 and IPv6 (via in_conninfo) 562 */ 563void tcp_hc_init(void); 564void tcp_hc_get(struct in_conninfo *, struct hc_metrics_lite *); 565u_long tcp_hc_getmtu(struct in_conninfo *); 566void tcp_hc_updatemtu(struct in_conninfo *, u_long); 567void tcp_hc_update(struct in_conninfo *, struct hc_metrics_lite *); 568 569extern struct pr_usrreqs tcp_usrreqs; 570extern u_long tcp_sendspace; 571extern u_long tcp_recvspace; 572tcp_seq tcp_new_isn(struct tcpcb *); 573 574int tcp_sack_option(struct tcpcb *,struct tcphdr *,u_char *,int); 575void tcp_update_sack_list(struct tcpcb *tp, tcp_seq rcv_laststart, tcp_seq rcv_lastend); 576void tcp_del_sackholes(struct tcpcb *, struct tcphdr *); 577void tcp_clean_sackreport(struct tcpcb *tp); 578void tcp_sack_adjust(struct tcpcb *tp); 579struct sackhole *tcp_sack_output(struct tcpcb *tp, int *sack_bytes_rexmt); 580int tcp_sacked_bytes(struct tcpcb *tp, int *lost_not_rexmitted); 581void tcp_sack_partialack(struct tcpcb *, struct tcphdr *); 582void tcp_free_sackholes(struct tcpcb *tp); 583int tcp_newreno(struct tcpcb *, struct tcphdr *); 584u_long tcp_seq_subtract(u_long, u_long ); 585 586#endif /* _KERNEL */ 587 588#endif /* _NETINET_TCP_VAR_H_ */ 589