tcp_var.h revision 169541
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 169541 2007-05-13 22:16:13Z andre $ 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/* Neighbor Discovery, Neighbor Unreachability Detection Upper layer hint. */ 79#ifdef INET6 80#define ND6_HINT(tp) \ 81do { \ 82 if ((tp) && (tp)->t_inpcb && \ 83 ((tp)->t_inpcb->inp_vflag & INP_IPV6) != 0) \ 84 nd6_nud_hint(NULL, NULL, 0); \ 85} while (0) 86#else 87#define ND6_HINT(tp) 88#endif 89 90/* 91 * Tcp control block, one per tcp; fields: 92 * Organized for 16 byte cacheline efficiency. 93 */ 94struct tcpcb { 95 struct tsegqe_head t_segq; /* segment reassembly queue */ 96 int t_segqlen; /* segment reassembly queue length */ 97 int t_dupacks; /* consecutive dup acks recd */ 98 99 struct tcp_timer *t_timers; /* retransmit timer */ 100 101 struct inpcb *t_inpcb; /* back pointer to internet pcb */ 102 int t_state; /* state of this connection */ 103 u_int t_flags; 104#define TF_ACKNOW 0x000001 /* ack peer immediately */ 105#define TF_DELACK 0x000002 /* ack, but try to delay it */ 106#define TF_NODELAY 0x000004 /* don't delay packets to coalesce */ 107#define TF_NOOPT 0x000008 /* don't use tcp options */ 108#define TF_SENTFIN 0x000010 /* have sent FIN */ 109#define TF_REQ_SCALE 0x000020 /* have/will request window scaling */ 110#define TF_RCVD_SCALE 0x000040 /* other side has requested scaling */ 111#define TF_REQ_TSTMP 0x000080 /* have/will request timestamps */ 112#define TF_RCVD_TSTMP 0x000100 /* a timestamp was received in SYN */ 113#define TF_SACK_PERMIT 0x000200 /* other side said I could SACK */ 114#define TF_NEEDSYN 0x000400 /* send SYN (implicit state) */ 115#define TF_NEEDFIN 0x000800 /* send FIN (implicit state) */ 116#define TF_NOPUSH 0x001000 /* don't push */ 117#define TF_MORETOCOME 0x010000 /* More data to be appended to sock */ 118#define TF_LQ_OVERFLOW 0x020000 /* listen queue overflow */ 119#define TF_LASTIDLE 0x040000 /* connection was previously idle */ 120#define TF_RXWIN0SENT 0x080000 /* sent a receiver win 0 in response */ 121#define TF_FASTRECOVERY 0x100000 /* in NewReno Fast Recovery */ 122#define TF_WASFRECOVERY 0x200000 /* was in NewReno Fast Recovery */ 123#define TF_SIGNATURE 0x400000 /* require MD5 digests (RFC2385) */ 124#define TF_FORCEDATA 0x800000 /* force out a byte */ 125#define TF_TSO 0x1000000 /* TSO enabled on this connection */ 126 127 tcp_seq snd_una; /* send unacknowledged */ 128 tcp_seq snd_max; /* highest sequence number sent; 129 * used to recognize retransmits 130 */ 131 tcp_seq snd_nxt; /* send next */ 132 tcp_seq snd_up; /* send urgent pointer */ 133 134 tcp_seq snd_wl1; /* window update seg seq number */ 135 tcp_seq snd_wl2; /* window update seg ack number */ 136 tcp_seq iss; /* initial send sequence number */ 137 tcp_seq irs; /* initial receive sequence number */ 138 139 tcp_seq rcv_nxt; /* receive next */ 140 tcp_seq rcv_adv; /* advertised window */ 141 u_long rcv_wnd; /* receive window */ 142 tcp_seq rcv_up; /* receive urgent pointer */ 143 144 u_long snd_wnd; /* send window */ 145 u_long snd_cwnd; /* congestion-controlled window */ 146 u_long snd_bwnd; /* bandwidth-controlled window */ 147 u_long snd_ssthresh; /* snd_cwnd size threshold for 148 * for slow start exponential to 149 * linear switch 150 */ 151 u_long snd_bandwidth; /* calculated bandwidth or 0 */ 152 tcp_seq snd_recover; /* for use in NewReno Fast Recovery */ 153 154 u_int t_maxopd; /* mss plus options */ 155 156 u_long t_rcvtime; /* inactivity time */ 157 u_long t_starttime; /* time connection was established */ 158 int t_rtttime; /* round trip time */ 159 tcp_seq t_rtseq; /* sequence number being timed */ 160 161 int t_bw_rtttime; /* used for bandwidth calculation */ 162 tcp_seq t_bw_rtseq; /* used for bandwidth calculation */ 163 164 int t_rxtcur; /* current retransmit value (ticks) */ 165 u_int t_maxseg; /* maximum segment size */ 166 int t_srtt; /* smoothed round-trip time */ 167 int t_rttvar; /* variance in round-trip time */ 168 169 int t_rxtshift; /* log(2) of rexmt exp. backoff */ 170 u_int t_rttmin; /* minimum rtt allowed */ 171 u_int t_rttbest; /* best rtt we've seen */ 172 u_long t_rttupdated; /* number of times rtt sampled */ 173 u_long max_sndwnd; /* largest window peer has offered */ 174 175 int t_softerror; /* possible error not yet reported */ 176/* out-of-band data */ 177 char t_oobflags; /* have some */ 178 char t_iobc; /* input character */ 179#define TCPOOB_HAVEDATA 0x01 180#define TCPOOB_HADDATA 0x02 181/* RFC 1323 variables */ 182 u_char snd_scale; /* window scaling for send window */ 183 u_char rcv_scale; /* window scaling for recv window */ 184 u_char request_r_scale; /* pending window scaling */ 185 u_int32_t ts_recent; /* timestamp echo data */ 186 u_long ts_recent_age; /* when last updated */ 187 u_int32_t ts_offset; /* our timestamp offset */ 188 189 tcp_seq last_ack_sent; 190/* experimental */ 191 u_long snd_cwnd_prev; /* cwnd prior to retransmit */ 192 u_long snd_ssthresh_prev; /* ssthresh prior to retransmit */ 193 tcp_seq snd_recover_prev; /* snd_recover prior to retransmit */ 194 u_long t_badrxtwin; /* window for retransmit recovery */ 195 u_char snd_limited; /* segments limited transmitted */ 196/* SACK related state */ 197 int snd_numholes; /* number of holes seen by sender */ 198 TAILQ_HEAD(sackhole_head, sackhole) snd_holes; 199 /* SACK scoreboard (sorted) */ 200 tcp_seq snd_fack; /* last seq number(+1) sack'd by rcv'r*/ 201 int rcv_numsacks; /* # distinct sack blks present */ 202 struct sackblk sackblks[MAX_SACK_BLKS]; /* seq nos. of sack blocks */ 203 tcp_seq sack_newdata; /* New data xmitted in this recovery 204 episode starts at this seq number */ 205 struct sackhint sackhint; /* SACK scoreboard hint */ 206 int t_rttlow; /* smallest observerved RTT */ 207 u_int32_t rfbuf_ts; /* recv buffer autoscaling timestamp */ 208 int rfbuf_cnt; /* recv buffer autoscaling byte count */ 209}; 210 211#define IN_FASTRECOVERY(tp) (tp->t_flags & TF_FASTRECOVERY) 212#define ENTER_FASTRECOVERY(tp) tp->t_flags |= TF_FASTRECOVERY 213#define EXIT_FASTRECOVERY(tp) tp->t_flags &= ~TF_FASTRECOVERY 214 215#ifdef TCP_SIGNATURE 216/* 217 * Defines which are needed by the xform_tcp module and tcp_[in|out]put 218 * for SADB verification and lookup. 219 */ 220#define TCP_SIGLEN 16 /* length of computed digest in bytes */ 221#define TCP_KEYLEN_MIN 1 /* minimum length of TCP-MD5 key */ 222#define TCP_KEYLEN_MAX 80 /* maximum length of TCP-MD5 key */ 223/* 224 * Only a single SA per host may be specified at this time. An SPI is 225 * needed in order for the KEY_ALLOCSA() lookup to work. 226 */ 227#define TCP_SIG_SPI 0x1000 228#endif /* TCP_SIGNATURE */ 229 230/* 231 * Structure to hold TCP options that are only used during segment 232 * processing (in tcp_input), but not held in the tcpcb. 233 * It's basically used to reduce the number of parameters 234 * to tcp_dooptions and tcp_addoptions. 235 * The binary order of the to_flags is relevant for packing of the 236 * options in tcp_addoptions. 237 */ 238struct tcpopt { 239 u_long to_flags; /* which options are present */ 240#define TOF_MSS 0x0001 /* maximum segment size */ 241#define TOF_SCALE 0x0002 /* window scaling */ 242#define TOF_SACKPERM 0x0004 /* SACK permitted */ 243#define TOF_TS 0x0010 /* timestamp */ 244#define TOF_SIGNATURE 0x0040 /* TCP-MD5 signature option (RFC2385) */ 245#define TOF_SACK 0x0080 /* Peer sent SACK option */ 246#define TOF_MAXOPT 0x0100 247 u_int32_t to_tsval; /* new timestamp */ 248 u_int32_t to_tsecr; /* reflected timestamp */ 249 u_int16_t to_mss; /* maximum segment size */ 250 u_int8_t to_wscale; /* window scaling */ 251 u_int8_t to_nsacks; /* number of SACK blocks */ 252 u_char *to_sacks; /* pointer to the first SACK blocks */ 253 u_char *to_signature; /* pointer to the TCP-MD5 signature */ 254}; 255 256/* 257 * Flags for tcp_dooptions. 258 */ 259#define TO_SYN 0x01 /* parse SYN-only options */ 260 261struct hc_metrics_lite { /* must stay in sync with hc_metrics */ 262 u_long rmx_mtu; /* MTU for this path */ 263 u_long rmx_ssthresh; /* outbound gateway buffer limit */ 264 u_long rmx_rtt; /* estimated round trip time */ 265 u_long rmx_rttvar; /* estimated rtt variance */ 266 u_long rmx_bandwidth; /* estimated bandwidth */ 267 u_long rmx_cwnd; /* congestion window */ 268 u_long rmx_sendpipe; /* outbound delay-bandwidth product */ 269 u_long rmx_recvpipe; /* inbound delay-bandwidth product */ 270}; 271 272#ifndef _NETINET_IN_PCB_H_ 273struct in_conninfo; 274#endif /* _NETINET_IN_PCB_H_ */ 275 276struct tcptw { 277 struct inpcb *tw_inpcb; /* XXX back pointer to internet pcb */ 278 tcp_seq snd_nxt; 279 tcp_seq rcv_nxt; 280 tcp_seq iss; 281 tcp_seq irs; 282 u_short last_win; /* cached window value */ 283 u_short tw_so_options; /* copy of so_options */ 284 struct ucred *tw_cred; /* user credentials */ 285 u_long t_recent; 286 u_int32_t ts_offset; /* our timestamp offset */ 287 u_long t_starttime; 288 int tw_time; 289 TAILQ_ENTRY(tcptw) tw_2msl; 290}; 291 292#define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb) 293#define intotw(ip) ((struct tcptw *)(ip)->inp_ppcb) 294#define sototcpcb(so) (intotcpcb(sotoinpcb(so))) 295 296/* 297 * The smoothed round-trip time and estimated variance 298 * are stored as fixed point numbers scaled by the values below. 299 * For convenience, these scales are also used in smoothing the average 300 * (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed). 301 * With these scales, srtt has 3 bits to the right of the binary point, 302 * and thus an "ALPHA" of 0.875. rttvar has 2 bits to the right of the 303 * binary point, and is smoothed with an ALPHA of 0.75. 304 */ 305#define TCP_RTT_SCALE 32 /* multiplier for srtt; 3 bits frac. */ 306#define TCP_RTT_SHIFT 5 /* shift for srtt; 3 bits frac. */ 307#define TCP_RTTVAR_SCALE 16 /* multiplier for rttvar; 2 bits */ 308#define TCP_RTTVAR_SHIFT 4 /* shift for rttvar; 2 bits */ 309#define TCP_DELTA_SHIFT 2 /* see tcp_input.c */ 310 311/* 312 * The initial retransmission should happen at rtt + 4 * rttvar. 313 * Because of the way we do the smoothing, srtt and rttvar 314 * will each average +1/2 tick of bias. When we compute 315 * the retransmit timer, we want 1/2 tick of rounding and 316 * 1 extra tick because of +-1/2 tick uncertainty in the 317 * firing of the timer. The bias will give us exactly the 318 * 1.5 tick we need. But, because the bias is 319 * statistical, we have to test that we don't drop below 320 * the minimum feasible timer (which is 2 ticks). 321 * This version of the macro adapted from a paper by Lawrence 322 * Brakmo and Larry Peterson which outlines a problem caused 323 * by insufficient precision in the original implementation, 324 * which results in inappropriately large RTO values for very 325 * fast networks. 326 */ 327#define TCP_REXMTVAL(tp) \ 328 max((tp)->t_rttmin, (((tp)->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT)) \ 329 + (tp)->t_rttvar) >> TCP_DELTA_SHIFT) 330 331/* 332 * TCP statistics. 333 * Many of these should be kept per connection, 334 * but that's inconvenient at the moment. 335 */ 336struct tcpstat { 337 u_long tcps_connattempt; /* connections initiated */ 338 u_long tcps_accepts; /* connections accepted */ 339 u_long tcps_connects; /* connections established */ 340 u_long tcps_drops; /* connections dropped */ 341 u_long tcps_conndrops; /* embryonic connections dropped */ 342 u_long tcps_minmssdrops; /* average minmss too low drops */ 343 u_long tcps_closed; /* conn. closed (includes drops) */ 344 u_long tcps_segstimed; /* segs where we tried to get rtt */ 345 u_long tcps_rttupdated; /* times we succeeded */ 346 u_long tcps_delack; /* delayed acks sent */ 347 u_long tcps_timeoutdrop; /* conn. dropped in rxmt timeout */ 348 u_long tcps_rexmttimeo; /* retransmit timeouts */ 349 u_long tcps_persisttimeo; /* persist timeouts */ 350 u_long tcps_keeptimeo; /* keepalive timeouts */ 351 u_long tcps_keepprobe; /* keepalive probes sent */ 352 u_long tcps_keepdrops; /* connections dropped in keepalive */ 353 354 u_long tcps_sndtotal; /* total packets sent */ 355 u_long tcps_sndpack; /* data packets sent */ 356 u_long tcps_sndbyte; /* data bytes sent */ 357 u_long tcps_sndrexmitpack; /* data packets retransmitted */ 358 u_long tcps_sndrexmitbyte; /* data bytes retransmitted */ 359 u_long tcps_sndrexmitbad; /* unnecessary packet retransmissions */ 360 u_long tcps_sndacks; /* ack-only packets sent */ 361 u_long tcps_sndprobe; /* window probes sent */ 362 u_long tcps_sndurg; /* packets sent with URG only */ 363 u_long tcps_sndwinup; /* window update-only packets sent */ 364 u_long tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */ 365 366 u_long tcps_rcvtotal; /* total packets received */ 367 u_long tcps_rcvpack; /* packets received in sequence */ 368 u_long tcps_rcvbyte; /* bytes received in sequence */ 369 u_long tcps_rcvbadsum; /* packets received with ccksum errs */ 370 u_long tcps_rcvbadoff; /* packets received with bad offset */ 371 u_long tcps_rcvmemdrop; /* packets dropped for lack of memory */ 372 u_long tcps_rcvshort; /* packets received too short */ 373 u_long tcps_rcvduppack; /* duplicate-only packets received */ 374 u_long tcps_rcvdupbyte; /* duplicate-only bytes received */ 375 u_long tcps_rcvpartduppack; /* packets with some duplicate data */ 376 u_long tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */ 377 u_long tcps_rcvoopack; /* out-of-order packets received */ 378 u_long tcps_rcvoobyte; /* out-of-order bytes received */ 379 u_long tcps_rcvpackafterwin; /* packets with data after window */ 380 u_long tcps_rcvbyteafterwin; /* bytes rcvd after window */ 381 u_long tcps_rcvafterclose; /* packets rcvd after "close" */ 382 u_long tcps_rcvwinprobe; /* rcvd window probe packets */ 383 u_long tcps_rcvdupack; /* rcvd duplicate acks */ 384 u_long tcps_rcvacktoomuch; /* rcvd acks for unsent data */ 385 u_long tcps_rcvackpack; /* rcvd ack packets */ 386 u_long tcps_rcvackbyte; /* bytes acked by rcvd acks */ 387 u_long tcps_rcvwinupd; /* rcvd window update packets */ 388 u_long tcps_pawsdrop; /* segments dropped due to PAWS */ 389 u_long tcps_predack; /* times hdr predict ok for acks */ 390 u_long tcps_preddat; /* times hdr predict ok for data pkts */ 391 u_long tcps_pcbcachemiss; 392 u_long tcps_cachedrtt; /* times cached RTT in route updated */ 393 u_long tcps_cachedrttvar; /* times cached rttvar updated */ 394 u_long tcps_cachedssthresh; /* times cached ssthresh updated */ 395 u_long tcps_usedrtt; /* times RTT initialized from route */ 396 u_long tcps_usedrttvar; /* times RTTVAR initialized from rt */ 397 u_long tcps_usedssthresh; /* times ssthresh initialized from rt*/ 398 u_long tcps_persistdrop; /* timeout in persist state */ 399 u_long tcps_badsyn; /* bogus SYN, e.g. premature ACK */ 400 u_long tcps_mturesent; /* resends due to MTU discovery */ 401 u_long tcps_listendrop; /* listen queue overflows */ 402 u_long tcps_badrst; /* ignored RSTs in the window */ 403 404 u_long tcps_sc_added; /* entry added to syncache */ 405 u_long tcps_sc_retransmitted; /* syncache entry was retransmitted */ 406 u_long tcps_sc_dupsyn; /* duplicate SYN packet */ 407 u_long tcps_sc_dropped; /* could not reply to packet */ 408 u_long tcps_sc_completed; /* successful extraction of entry */ 409 u_long tcps_sc_bucketoverflow; /* syncache per-bucket limit hit */ 410 u_long tcps_sc_cacheoverflow; /* syncache cache limit hit */ 411 u_long tcps_sc_reset; /* RST removed entry from syncache */ 412 u_long tcps_sc_stale; /* timed out or listen socket gone */ 413 u_long tcps_sc_aborted; /* syncache entry aborted */ 414 u_long tcps_sc_badack; /* removed due to bad ACK */ 415 u_long tcps_sc_unreach; /* ICMP unreachable received */ 416 u_long tcps_sc_zonefail; /* zalloc() failed */ 417 u_long tcps_sc_sendcookie; /* SYN cookie sent */ 418 u_long tcps_sc_recvcookie; /* SYN cookie received */ 419 420 u_long tcps_hc_added; /* entry added to hostcache */ 421 u_long tcps_hc_bucketoverflow; /* hostcache per bucket limit hit */ 422 423 u_long tcps_finwait2_drops; /* Drop FIN_WAIT_2 connection after time limit */ 424 425 /* SACK related stats */ 426 u_long tcps_sack_recovery_episode; /* SACK recovery episodes */ 427 u_long tcps_sack_rexmits; /* SACK rexmit segments */ 428 u_long tcps_sack_rexmit_bytes; /* SACK rexmit bytes */ 429 u_long tcps_sack_rcv_blocks; /* SACK blocks (options) received */ 430 u_long tcps_sack_send_blocks; /* SACK blocks (options) sent */ 431 u_long tcps_sack_sboverflow; /* times scoreboard overflowed */ 432}; 433 434/* 435 * TCB structure exported to user-land via sysctl(3). 436 * Evil hack: declare only if in_pcb.h and sys/socketvar.h have been 437 * included. Not all of our clients do. 438 */ 439#if defined(_NETINET_IN_PCB_H_) && defined(_SYS_SOCKETVAR_H_) 440struct xtcpcb { 441 size_t xt_len; 442 struct inpcb xt_inp; 443 struct tcpcb xt_tp; 444 struct xsocket xt_socket; 445 u_quad_t xt_alignment_hack; 446}; 447#endif 448 449/* 450 * Names for TCP sysctl objects 451 */ 452#define TCPCTL_DO_RFC1323 1 /* use RFC-1323 extensions */ 453#define TCPCTL_MSSDFLT 3 /* MSS default */ 454#define TCPCTL_STATS 4 /* statistics (read-only) */ 455#define TCPCTL_RTTDFLT 5 /* default RTT estimate */ 456#define TCPCTL_KEEPIDLE 6 /* keepalive idle timer */ 457#define TCPCTL_KEEPINTVL 7 /* interval to send keepalives */ 458#define TCPCTL_SENDSPACE 8 /* send buffer space */ 459#define TCPCTL_RECVSPACE 9 /* receive buffer space */ 460#define TCPCTL_KEEPINIT 10 /* timeout for establishing syn */ 461#define TCPCTL_PCBLIST 11 /* list of all outstanding PCBs */ 462#define TCPCTL_DELACKTIME 12 /* time before sending delayed ACK */ 463#define TCPCTL_V6MSSDFLT 13 /* MSS default for IPv6 */ 464#define TCPCTL_SACK 14 /* Selective Acknowledgement,rfc 2018 */ 465#define TCPCTL_DROP 15 /* drop tcp connection */ 466#define TCPCTL_MAXID 16 467#define TCPCTL_FINWAIT2_TIMEOUT 17 468 469#define TCPCTL_NAMES { \ 470 { 0, 0 }, \ 471 { "rfc1323", CTLTYPE_INT }, \ 472 { "mssdflt", CTLTYPE_INT }, \ 473 { "stats", CTLTYPE_STRUCT }, \ 474 { "rttdflt", CTLTYPE_INT }, \ 475 { "keepidle", CTLTYPE_INT }, \ 476 { "keepintvl", CTLTYPE_INT }, \ 477 { "sendspace", CTLTYPE_INT }, \ 478 { "recvspace", CTLTYPE_INT }, \ 479 { "keepinit", CTLTYPE_INT }, \ 480 { "pcblist", CTLTYPE_STRUCT }, \ 481 { "delacktime", CTLTYPE_INT }, \ 482 { "v6mssdflt", CTLTYPE_INT }, \ 483 { "maxid", CTLTYPE_INT }, \ 484} 485 486 487#ifdef _KERNEL 488#ifdef SYSCTL_DECL 489SYSCTL_DECL(_net_inet_tcp); 490SYSCTL_DECL(_net_inet_tcp_sack); 491#endif 492 493extern struct inpcbhead tcb; /* head of queue of active tcpcb's */ 494extern struct inpcbinfo tcbinfo; 495extern struct tcpstat tcpstat; /* tcp statistics */ 496extern int tcp_mssdflt; /* XXX */ 497extern int tcp_minmss; 498extern int tcp_delack_enabled; 499extern int tcp_do_newreno; 500extern int path_mtu_discovery; 501extern int ss_fltsz; 502extern int ss_fltsz_local; 503 504extern int tcp_do_sack; /* SACK enabled/disabled */ 505 506int tcp_addoptions(struct tcpopt *, u_char *); 507struct tcpcb * 508 tcp_close(struct tcpcb *); 509void tcp_discardcb(struct tcpcb *); 510void tcp_twstart(struct tcpcb *); 511#if 0 512int tcp_twrecycleable(struct tcptw *tw); 513#endif 514void tcp_twclose(struct tcptw *_tw, int _reuse); 515void tcp_ctlinput(int, struct sockaddr *, void *); 516int tcp_ctloutput(struct socket *, struct sockopt *); 517struct tcpcb * 518 tcp_drop(struct tcpcb *, int); 519void tcp_drain(void); 520void tcp_fasttimo(void); 521void tcp_init(void); 522void tcp_fini(void *); 523int tcp_reass(struct tcpcb *, struct tcphdr *, int *, struct mbuf *); 524void tcp_reass_init(void); 525void tcp_input(struct mbuf *, int); 526u_long tcp_maxmtu(struct in_conninfo *, int *); 527u_long tcp_maxmtu6(struct in_conninfo *, int *); 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); 539void tcp_tw_init(void); 540void tcp_tw_zone_change(void); 541int tcp_twrespond(struct tcptw *, int); 542void tcp_setpersist(struct tcpcb *); 543#ifdef TCP_SIGNATURE 544int tcp_signature_compute(struct mbuf *, int, int, int, u_char *, u_int); 545#endif 546void tcp_slowtimo(void); 547struct tcptemp * 548 tcpip_maketemplate(struct inpcb *); 549void tcpip_fillheaders(struct inpcb *, void *, void *); 550void tcp_timer_activate(struct tcpcb *, int, u_int); 551int tcp_timer_active(struct tcpcb *, int); 552void tcp_trace(short, short, struct tcpcb *, void *, struct tcphdr *, int); 553void tcp_xmit_bandwidth_limit(struct tcpcb *tp, tcp_seq ack_seq); 554void syncache_init(void); 555void syncache_unreach(struct in_conninfo *, struct tcphdr *); 556int syncache_expand(struct in_conninfo *, struct tcpopt *, 557 struct tcphdr *, struct socket **, struct mbuf *); 558void syncache_add(struct in_conninfo *, struct tcpopt *, 559 struct tcphdr *, struct inpcb *, struct socket **, struct mbuf *); 560void syncache_chkrst(struct in_conninfo *, struct tcphdr *); 561void syncache_badack(struct in_conninfo *); 562/* 563 * All tcp_hc_* functions are IPv4 and IPv6 (via in_conninfo) 564 */ 565void tcp_hc_init(void); 566void tcp_hc_get(struct in_conninfo *, struct hc_metrics_lite *); 567u_long tcp_hc_getmtu(struct in_conninfo *); 568void tcp_hc_updatemtu(struct in_conninfo *, u_long); 569void tcp_hc_update(struct in_conninfo *, struct hc_metrics_lite *); 570 571extern struct pr_usrreqs tcp_usrreqs; 572extern u_long tcp_sendspace; 573extern u_long tcp_recvspace; 574tcp_seq tcp_new_isn(struct tcpcb *); 575 576void tcp_sack_doack(struct tcpcb *, struct tcpopt *, tcp_seq); 577void tcp_update_sack_list(struct tcpcb *tp, tcp_seq rcv_laststart, tcp_seq rcv_lastend); 578void tcp_clean_sackreport(struct tcpcb *tp); 579void tcp_sack_adjust(struct tcpcb *tp); 580struct sackhole *tcp_sack_output(struct tcpcb *tp, int *sack_bytes_rexmt); 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