tcp_var.h revision 1.163
1 /* $NetBSD: tcp_var.h,v 1.163 2011/04/14 15:55:46 yamt Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * @(#)COPYRIGHT 1.1 (NRL) 17 January 1995 34 * 35 * NRL grants permission for redistribution and use in source and binary 36 * forms, with or without modification, of the software and documentation 37 * created at NRL provided that the following conditions are met: 38 * 39 * 1. Redistributions of source code must retain the above copyright 40 * notice, this list of conditions and the following disclaimer. 41 * 2. Redistributions in binary form must reproduce the above copyright 42 * notice, this list of conditions and the following disclaimer in the 43 * documentation and/or other materials provided with the distribution. 44 * 3. All advertising materials mentioning features or use of this software 45 * must display the following acknowledgements: 46 * This product includes software developed by the University of 47 * California, Berkeley and its contributors. 48 * This product includes software developed at the Information 49 * Technology Division, US Naval Research Laboratory. 50 * 4. Neither the name of the NRL nor the names of its contributors 51 * may be used to endorse or promote products derived from this software 52 * without specific prior written permission. 53 * 54 * THE SOFTWARE PROVIDED BY NRL IS PROVIDED BY NRL AND CONTRIBUTORS ``AS 55 * IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 56 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 57 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL NRL OR 58 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 59 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 60 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 61 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 62 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 63 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 64 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 65 * 66 * The views and conclusions contained in the software and documentation 67 * are those of the authors and should not be interpreted as representing 68 * official policies, either expressed or implied, of the US Naval 69 * Research Laboratory (NRL). 70 */ 71 72 /*- 73 * Copyright (c) 1997, 1998, 1999, 2001, 2005 The NetBSD Foundation, Inc. 74 * All rights reserved. 75 * 76 * This code is derived from software contributed to The NetBSD Foundation 77 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 78 * NASA Ames Research Center. 79 * This code is derived from software contributed to The NetBSD Foundation 80 * by Charles M. Hannum. 81 * 82 * Redistribution and use in source and binary forms, with or without 83 * modification, are permitted provided that the following conditions 84 * are met: 85 * 1. Redistributions of source code must retain the above copyright 86 * notice, this list of conditions and the following disclaimer. 87 * 2. Redistributions in binary form must reproduce the above copyright 88 * notice, this list of conditions and the following disclaimer in the 89 * documentation and/or other materials provided with the distribution. 90 * 91 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 92 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 93 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 94 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 95 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 96 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 97 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 98 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 99 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 100 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 101 * POSSIBILITY OF SUCH DAMAGE. 102 */ 103 104 /* 105 * Copyright (c) 1982, 1986, 1993, 1994, 1995 106 * The Regents of the University of California. All rights reserved. 107 * 108 * Redistribution and use in source and binary forms, with or without 109 * modification, are permitted provided that the following conditions 110 * are met: 111 * 1. Redistributions of source code must retain the above copyright 112 * notice, this list of conditions and the following disclaimer. 113 * 2. Redistributions in binary form must reproduce the above copyright 114 * notice, this list of conditions and the following disclaimer in the 115 * documentation and/or other materials provided with the distribution. 116 * 3. Neither the name of the University nor the names of its contributors 117 * may be used to endorse or promote products derived from this software 118 * without specific prior written permission. 119 * 120 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 121 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 122 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 123 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 124 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 125 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 126 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 127 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 128 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 129 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 130 * SUCH DAMAGE. 131 * 132 * @(#)tcp_var.h 8.4 (Berkeley) 5/24/95 133 */ 134 135 #ifndef _NETINET_TCP_VAR_H_ 136 #define _NETINET_TCP_VAR_H_ 137 138 #if defined(_KERNEL_OPT) 139 #include "opt_inet.h" 140 #include "opt_mbuftrace.h" 141 #include "rnd.h" 142 #endif 143 144 /* 145 * Kernel variables for tcp. 146 */ 147 148 #include <sys/callout.h> 149 150 #ifdef TCP_SIGNATURE 151 /* 152 * Defines which are needed by the xform_tcp module and tcp_[in|out]put 153 * for SADB verification and lookup. 154 */ 155 #define TCP_SIGLEN 16 /* length of computed digest in bytes */ 156 #define TCP_KEYLEN_MIN 1 /* minimum length of TCP-MD5 key */ 157 #define TCP_KEYLEN_MAX 80 /* maximum length of TCP-MD5 key */ 158 /* 159 * Only a single SA per host may be specified at this time. An SPI is 160 * needed in order for the KEY_ALLOCSA() lookup to work. 161 */ 162 #define TCP_SIG_SPI 0x1000 163 #endif /* TCP_SIGNATURE */ 164 165 /* 166 * SACK option block. 167 */ 168 struct sackblk { 169 tcp_seq left; /* Left edge of sack block. */ 170 tcp_seq right; /* Right edge of sack block. */ 171 }; 172 173 TAILQ_HEAD(sackhead, sackhole); 174 struct sackhole { 175 tcp_seq start; 176 tcp_seq end; 177 tcp_seq rxmit; 178 179 TAILQ_ENTRY(sackhole) sackhole_q; 180 }; 181 182 /* 183 * Tcp control block, one per tcp; fields: 184 */ 185 struct tcpcb { 186 int t_family; /* address family on the wire */ 187 struct ipqehead segq; /* sequencing queue */ 188 int t_segqlen; /* length of the above */ 189 callout_t t_timer[TCPT_NTIMERS];/* tcp timers */ 190 short t_state; /* state of this connection */ 191 short t_rxtshift; /* log(2) of rexmt exp. backoff */ 192 uint32_t t_rxtcur; /* current retransmit value */ 193 short t_dupacks; /* consecutive dup acks recd */ 194 /* 195 * t_partialacks: 196 * <0 not in fast recovery. 197 * ==0 in fast recovery. has not received partial acks 198 * >0 in fast recovery. has received partial acks 199 */ 200 short t_partialacks; /* partials acks during fast rexmit */ 201 u_short t_peermss; /* peer's maximum segment size */ 202 u_short t_ourmss; /* our's maximum segment size */ 203 u_short t_segsz; /* current segment size in use */ 204 char t_force; /* 1 if forcing out a byte */ 205 u_int t_flags; 206 #define TF_ACKNOW 0x0001 /* ack peer immediately */ 207 #define TF_DELACK 0x0002 /* ack, but try to delay it */ 208 #define TF_NODELAY 0x0004 /* don't delay packets to coalesce */ 209 #define TF_NOOPT 0x0008 /* don't use tcp options */ 210 #define TF_REQ_SCALE 0x0020 /* have/will request window scaling */ 211 #define TF_RCVD_SCALE 0x0040 /* other side has requested scaling */ 212 #define TF_REQ_TSTMP 0x0080 /* have/will request timestamps */ 213 #define TF_RCVD_TSTMP 0x0100 /* a timestamp was received in SYN */ 214 #define TF_SACK_PERMIT 0x0200 /* other side said I could SACK */ 215 #define TF_SYN_REXMT 0x0400 /* rexmit timer fired on SYN */ 216 #define TF_WILL_SACK 0x0800 /* try to use SACK */ 217 #define TF_REASSEMBLING 0x1000 /* we're busy reassembling */ 218 #define TF_DEAD 0x2000 /* dead and to-be-released */ 219 #define TF_PMTUD_PEND 0x4000 /* Path MTU Discovery pending */ 220 #define TF_ECN_PERMIT 0x10000 /* other side said is ECN-ready */ 221 #define TF_ECN_SND_CWR 0x20000 /* ECN CWR in queue */ 222 #define TF_ECN_SND_ECE 0x40000 /* ECN ECE in queue */ 223 #define TF_SIGNATURE 0x400000 /* require MD5 digests (RFC2385) */ 224 225 226 struct mbuf *t_template; /* skeletal packet for transmit */ 227 struct inpcb *t_inpcb; /* back pointer to internet pcb */ 228 struct in6pcb *t_in6pcb; /* back pointer to internet pcb */ 229 callout_t t_delack_ch; /* delayed ACK callout */ 230 /* 231 * The following fields are used as in the protocol specification. 232 * See RFC793, Dec. 1981, page 21. 233 */ 234 /* send sequence variables */ 235 tcp_seq snd_una; /* send unacknowledged */ 236 tcp_seq snd_nxt; /* send next */ 237 tcp_seq snd_up; /* send urgent pointer */ 238 tcp_seq snd_wl1; /* window update seg seq number */ 239 tcp_seq snd_wl2; /* window update seg ack number */ 240 tcp_seq iss; /* initial send sequence number */ 241 u_long snd_wnd; /* send window */ 242 /* 243 * snd_recover 244 * it's basically same as the "recover" variable in RFC 2852 (NewReno). 245 * when entering fast retransmit, it's set to snd_max. 246 * newreno uses this to detect partial ack. 247 * snd_high 248 * it's basically same as the "send_high" variable in RFC 2852 (NewReno). 249 * on each RTO, it's set to snd_max. 250 * newreno uses this to avoid false fast retransmits. 251 */ 252 tcp_seq snd_recover; 253 tcp_seq snd_high; 254 /* receive sequence variables */ 255 u_long rcv_wnd; /* receive window */ 256 tcp_seq rcv_nxt; /* receive next */ 257 tcp_seq rcv_up; /* receive urgent pointer */ 258 tcp_seq irs; /* initial receive sequence number */ 259 /* 260 * Additional variables for this implementation. 261 */ 262 /* receive variables */ 263 tcp_seq rcv_adv; /* advertised window */ 264 265 /* 266 * retransmit variables 267 * 268 * snd_max 269 * the highest sequence number we've ever sent. 270 * used to recognize retransmits. 271 */ 272 tcp_seq snd_max; 273 274 /* congestion control (for slow start, source quench, retransmit after loss) */ 275 u_long snd_cwnd; /* congestion-controlled window */ 276 u_long snd_ssthresh; /* snd_cwnd size threshhold for 277 * for slow start exponential to 278 * linear switch 279 */ 280 /* auto-sizing variables */ 281 u_int rfbuf_cnt; /* recv buffer autoscaling byte count */ 282 uint32_t rfbuf_ts; /* recv buffer autoscaling timestamp */ 283 284 /* 285 * transmit timing stuff. See below for scale of srtt and rttvar. 286 * "Variance" is actually smoothed difference. 287 */ 288 uint32_t t_rcvtime; /* time last segment received */ 289 uint32_t t_rtttime; /* time we started measuring rtt */ 290 tcp_seq t_rtseq; /* sequence number being timed */ 291 int32_t t_srtt; /* smoothed round-trip time */ 292 int32_t t_rttvar; /* variance in round-trip time */ 293 uint32_t t_rttmin; /* minimum rtt allowed */ 294 u_long max_sndwnd; /* largest window peer has offered */ 295 296 /* out-of-band data */ 297 char t_oobflags; /* have some */ 298 char t_iobc; /* input character */ 299 #define TCPOOB_HAVEDATA 0x01 300 #define TCPOOB_HADDATA 0x02 301 short t_softerror; /* possible error not yet reported */ 302 303 /* RFC 1323 variables */ 304 u_char snd_scale; /* window scaling for send window */ 305 u_char rcv_scale; /* window scaling for recv window */ 306 u_char request_r_scale; /* pending window scaling */ 307 u_char requested_s_scale; 308 u_int32_t ts_recent; /* timestamp echo data */ 309 u_int32_t ts_recent_age; /* when last updated */ 310 u_int32_t ts_timebase; /* our timebase */ 311 tcp_seq last_ack_sent; 312 313 /* RFC 3465 variables */ 314 u_long t_bytes_acked; /* ABC "bytes_acked" parameter */ 315 316 /* SACK stuff */ 317 #define TCP_SACK_MAX 3 318 #define TCPSACK_NONE 0 319 #define TCPSACK_HAVED 1 320 u_char rcv_sack_flags; /* SACK flags. */ 321 struct sackblk rcv_dsack_block; /* RX D-SACK block. */ 322 struct ipqehead timeq; /* time sequenced queue. */ 323 struct sackhead snd_holes; /* TX SACK holes. */ 324 int snd_numholes; /* Number of TX SACK holes. */ 325 tcp_seq rcv_lastsack; /* last seq number(+1) sack'd by rcv'r*/ 326 tcp_seq sack_newdata; /* New data xmitted in this recovery 327 episode starts at this seq number*/ 328 tcp_seq snd_fack; /* FACK TCP. Forward-most data held by 329 peer. */ 330 331 /* pointer for syn cache entries*/ 332 LIST_HEAD(, syn_cache) t_sc; /* list of entries by this tcb */ 333 334 /* prediction of next mbuf when using large window sizes */ 335 struct mbuf *t_lastm; /* last mbuf that data was sent from */ 336 int t_inoff; /* data offset in previous mbuf */ 337 int t_lastoff; /* last data address in mbuf chain */ 338 int t_lastlen; /* last length read from mbuf chain */ 339 340 /* Path-MTU discovery blackhole detection */ 341 int t_mtudisc; /* perform mtudisc for this tcb */ 342 /* Path-MTU Discovery Information */ 343 u_int t_pmtud_mss_acked; /* MSS acked, lower bound for MTU */ 344 u_int t_pmtud_mtu_sent; /* MTU used, upper bound for MTU */ 345 tcp_seq t_pmtud_th_seq; /* TCP SEQ from ICMP payload */ 346 u_int t_pmtud_nextmtu; /* Advertised Next-Hop MTU from ICMP */ 347 u_short t_pmtud_ip_len; /* IP length from ICMP payload */ 348 u_short t_pmtud_ip_hl; /* IP header length from ICMP payload */ 349 350 uint8_t t_ecn_retries; /* # of ECN setup retries */ 351 352 const struct tcp_congctl *t_congctl; /* per TCB congctl algorithm */ 353 354 /* Keepalive per socket */ 355 u_int t_keepinit; 356 u_int t_keepidle; 357 u_int t_keepintvl; 358 u_int t_keepcnt; 359 u_int t_maxidle; /* t_keepcnt * t_keepintvl */ 360 361 }; 362 363 /* 364 * Macros to aid ECN TCP. 365 */ 366 #define TCP_ECN_ALLOWED(tp) (tp->t_flags & TF_ECN_PERMIT) 367 368 /* 369 * Macros to aid SACK/FACK TCP. 370 */ 371 #define TCP_SACK_ENABLED(tp) (tp->t_flags & TF_WILL_SACK) 372 #define TCP_FACK_FASTRECOV(tp) \ 373 (TCP_SACK_ENABLED(tp) && \ 374 (SEQ_GT(tp->snd_fack, tp->snd_una + tcprexmtthresh * tp->t_segsz))) 375 376 #ifdef _KERNEL 377 /* 378 * TCP reassembly queue locks. 379 */ 380 static __inline int tcp_reass_lock_try (struct tcpcb *) 381 __unused; 382 static __inline void tcp_reass_unlock (struct tcpcb *) 383 __unused; 384 385 static __inline int 386 tcp_reass_lock_try(struct tcpcb *tp) 387 { 388 int s; 389 390 /* 391 * Use splvm() -- we're blocking things that would cause 392 * mbuf allocation. 393 */ 394 s = splvm(); 395 if (tp->t_flags & TF_REASSEMBLING) { 396 splx(s); 397 return (0); 398 } 399 tp->t_flags |= TF_REASSEMBLING; 400 splx(s); 401 return (1); 402 } 403 404 static __inline void 405 tcp_reass_unlock(struct tcpcb *tp) 406 { 407 int s; 408 409 s = splvm(); 410 tp->t_flags &= ~TF_REASSEMBLING; 411 splx(s); 412 } 413 414 #ifdef DIAGNOSTIC 415 #define TCP_REASS_LOCK(tp) \ 416 do { \ 417 if (tcp_reass_lock_try(tp) == 0) { \ 418 printf("%s:%d: tcpcb %p reass already locked\n", \ 419 __FILE__, __LINE__, tp); \ 420 panic("tcp_reass_lock"); \ 421 } \ 422 } while (/*CONSTCOND*/ 0) 423 #define TCP_REASS_LOCK_CHECK(tp) \ 424 do { \ 425 if (((tp)->t_flags & TF_REASSEMBLING) == 0) { \ 426 printf("%s:%d: tcpcb %p reass lock not held\n", \ 427 __FILE__, __LINE__, tp); \ 428 panic("tcp reass lock check"); \ 429 } \ 430 } while (/*CONSTCOND*/ 0) 431 #else 432 #define TCP_REASS_LOCK(tp) (void) tcp_reass_lock_try((tp)) 433 #define TCP_REASS_LOCK_CHECK(tp) /* nothing */ 434 #endif 435 436 #define TCP_REASS_UNLOCK(tp) tcp_reass_unlock((tp)) 437 #endif /* _KERNEL */ 438 439 /* 440 * Queue for delayed ACK processing. 441 */ 442 #ifdef _KERNEL 443 extern int tcp_delack_ticks; 444 void tcp_delack(void *); 445 446 #define TCP_RESTART_DELACK(tp) \ 447 callout_reset(&(tp)->t_delack_ch, tcp_delack_ticks, \ 448 tcp_delack, tp) 449 450 #define TCP_SET_DELACK(tp) \ 451 do { \ 452 if (((tp)->t_flags & TF_DELACK) == 0) { \ 453 (tp)->t_flags |= TF_DELACK; \ 454 TCP_RESTART_DELACK(tp); \ 455 } \ 456 } while (/*CONSTCOND*/0) 457 458 #define TCP_CLEAR_DELACK(tp) \ 459 do { \ 460 if ((tp)->t_flags & TF_DELACK) { \ 461 (tp)->t_flags &= ~TF_DELACK; \ 462 callout_stop(&(tp)->t_delack_ch); \ 463 } \ 464 } while (/*CONSTCOND*/0) 465 #endif /* _KERNEL */ 466 467 /* 468 * Compute the current timestamp for a connection. 469 */ 470 #define TCP_TIMESTAMP(tp) (tcp_now - (tp)->ts_timebase) 471 472 /* 473 * Handy way of passing around TCP option info. 474 */ 475 struct tcp_opt_info { 476 int ts_present; 477 u_int32_t ts_val; 478 u_int32_t ts_ecr; 479 u_int16_t maxseg; 480 }; 481 482 #define TOF_SIGNATURE 0x0040 /* signature option present */ 483 #define TOF_SIGLEN 0x0080 /* sigature length valid (RFC2385) */ 484 485 /* 486 * Data for the TCP compressed state engine. 487 */ 488 union syn_cache_sa { 489 struct sockaddr sa; 490 struct sockaddr_in sin; 491 #if 1 /*def INET6*/ 492 struct sockaddr_in6 sin6; 493 #endif 494 }; 495 496 struct syn_cache { 497 TAILQ_ENTRY(syn_cache) sc_bucketq; /* link on bucket list */ 498 callout_t sc_timer; /* rexmt timer */ 499 struct route sc_route; 500 long sc_win; /* advertised window */ 501 int sc_bucketidx; /* our bucket index */ 502 u_int32_t sc_hash; 503 u_int32_t sc_timestamp; /* timestamp from SYN */ 504 u_int32_t sc_timebase; /* our local timebase */ 505 union syn_cache_sa sc_src; 506 union syn_cache_sa sc_dst; 507 tcp_seq sc_irs; 508 tcp_seq sc_iss; 509 u_int sc_rxtcur; /* current rxt timeout */ 510 u_int sc_rxttot; /* total time spend on queues */ 511 u_short sc_rxtshift; /* for computing backoff */ 512 u_short sc_flags; 513 514 #define SCF_UNREACH 0x0001 /* we've had an unreach error */ 515 #define SCF_TIMESTAMP 0x0002 /* peer will do timestamps */ 516 #define SCF_DEAD 0x0004 /* this entry to be released */ 517 #define SCF_SACK_PERMIT 0x0008 /* peer will do SACK */ 518 #define SCF_ECN_PERMIT 0x0010 /* peer will do ECN */ 519 #define SCF_SIGNATURE 0x40 /* send MD5 digests */ 520 521 struct mbuf *sc_ipopts; /* IP options */ 522 u_int16_t sc_peermaxseg; 523 u_int16_t sc_ourmaxseg; 524 u_int8_t sc_request_r_scale : 4, 525 sc_requested_s_scale : 4; 526 527 struct tcpcb *sc_tp; /* tcb for listening socket */ 528 LIST_ENTRY(syn_cache) sc_tpq; /* list of entries by same tp */ 529 }; 530 531 struct syn_cache_head { 532 TAILQ_HEAD(, syn_cache) sch_bucket; /* bucket entries */ 533 u_short sch_length; /* # entries in bucket */ 534 }; 535 536 #define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb) 537 #ifdef INET6 538 #define in6totcpcb(ip) ((struct tcpcb *)(ip)->in6p_ppcb) 539 #endif 540 #ifndef INET6 541 #define sototcpcb(so) (intotcpcb(sotoinpcb(so))) 542 #else 543 #define sototcpcb(so) (((so)->so_proto->pr_domain->dom_family == AF_INET) \ 544 ? intotcpcb(sotoinpcb(so)) \ 545 : in6totcpcb(sotoin6pcb(so))) 546 #endif 547 548 /* 549 * The smoothed round-trip time and estimated variance 550 * are stored as fixed point numbers scaled by the values below. 551 * For convenience, these scales are also used in smoothing the average 552 * (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed). 553 * With these scales, srtt has 3 bits to the right of the binary point, 554 * and thus an "ALPHA" of 0.875. rttvar has 2 bits to the right of the 555 * binary point, and is smoothed with an ALPHA of 0.75. 556 */ 557 #define TCP_RTT_SHIFT 3 /* shift for srtt; 3 bits frac. */ 558 #define TCP_RTTVAR_SHIFT 2 /* multiplier for rttvar; 2 bits */ 559 560 /* 561 * The initial retransmission should happen at rtt + 4 * rttvar. 562 * Because of the way we do the smoothing, srtt and rttvar 563 * will each average +1/2 tick of bias. When we compute 564 * the retransmit timer, we want 1/2 tick of rounding and 565 * 1 extra tick because of +-1/2 tick uncertainty in the 566 * firing of the timer. The bias will give us exactly the 567 * 1.5 tick we need. But, because the bias is 568 * statistical, we have to test that we don't drop below 569 * the minimum feasible timer (which is 2 ticks). 570 * This macro assumes that the value of 1<<TCP_RTTVAR_SHIFT 571 * is the same as the multiplier for rttvar. 572 */ 573 #define TCP_REXMTVAL(tp) \ 574 ((((tp)->t_srtt >> TCP_RTT_SHIFT) + (tp)->t_rttvar) >> 2) 575 576 /* 577 * Compute the initial window for slow start. 578 */ 579 #define TCP_INITIAL_WINDOW(iw, segsz) \ 580 (((iw) == 0) ? (min(4 * (segsz), max(2 * (segsz), 4380))) : \ 581 ((segsz) * (iw))) 582 583 /* 584 * TCP statistics. 585 * Each counter is an unsigned 64-bit value. 586 * 587 * Many of these should be kept per connection, but that's inconvenient 588 * at the moment. 589 */ 590 #define TCP_STAT_CONNATTEMPT 0 /* connections initiated */ 591 #define TCP_STAT_ACCEPTS 1 /* connections accepted */ 592 #define TCP_STAT_CONNECTS 2 /* connections established */ 593 #define TCP_STAT_DROPS 3 /* connections dropped */ 594 #define TCP_STAT_CONNDROPS 4 /* embryonic connections dropped */ 595 #define TCP_STAT_CLOSED 5 /* conn. closed (includes drops) */ 596 #define TCP_STAT_SEGSTIMED 6 /* segs where we tried to get rtt */ 597 #define TCP_STAT_RTTUPDATED 7 /* times we succeeded */ 598 #define TCP_STAT_DELACK 8 /* delayed ACKs sent */ 599 #define TCP_STAT_TIMEOUTDROP 9 /* conn. dropped in rxmt timeout */ 600 #define TCP_STAT_REXMTTIMEO 10 /* retransmit timeouts */ 601 #define TCP_STAT_PERSISTTIMEO 11 /* persist timeouts */ 602 #define TCP_STAT_KEEPTIMEO 12 /* keepalive timeouts */ 603 #define TCP_STAT_KEEPPROBE 13 /* keepalive probes sent */ 604 #define TCP_STAT_KEEPDROPS 14 /* connections dropped in keepalive */ 605 #define TCP_STAT_PERSISTDROPS 15 /* connections dropped in persist */ 606 #define TCP_STAT_CONNSDRAINED 16 /* connections drained due to memory 607 shortage */ 608 #define TCP_STAT_PMTUBLACKHOLE 17 /* PMTUD blackhole detected */ 609 #define TCP_STAT_SNDTOTAL 18 /* total packets sent */ 610 #define TCP_STAT_SNDPACK 19 /* data packlets sent */ 611 #define TCP_STAT_SNDBYTE 20 /* data bytes sent */ 612 #define TCP_STAT_SNDREXMITPACK 21 /* data packets retransmitted */ 613 #define TCP_STAT_SNDREXMITBYTE 22 /* data bytes retransmitted */ 614 #define TCP_STAT_SNDACKS 23 /* ACK-only packets sent */ 615 #define TCP_STAT_SNDPROBE 24 /* window probes sent */ 616 #define TCP_STAT_SNDURG 25 /* packets sent with URG only */ 617 #define TCP_STAT_SNDWINUP 26 /* window update-only packets sent */ 618 #define TCP_STAT_SNDCTRL 27 /* control (SYN|FIN|RST) packets sent */ 619 #define TCP_STAT_RCVTOTAL 28 /* total packets received */ 620 #define TCP_STAT_RCVPACK 29 /* packets received in sequence */ 621 #define TCP_STAT_RCVBYTE 30 /* bytes received in sequence */ 622 #define TCP_STAT_RCVBADSUM 31 /* packets received with cksum errs */ 623 #define TCP_STAT_RCVBADOFF 32 /* packets received with bad offset */ 624 #define TCP_STAT_RCVMEMDROP 33 /* packets dropped for lack of memory */ 625 #define TCP_STAT_RCVSHORT 34 /* packets received too short */ 626 #define TCP_STAT_RCVDUPPACK 35 /* duplicate-only packets received */ 627 #define TCP_STAT_RCVDUPBYTE 36 /* duplicate-only bytes received */ 628 #define TCP_STAT_RCVPARTDUPPACK 37 /* packets with some duplicate data */ 629 #define TCP_STAT_RCVPARTDUPBYTE 38 /* dup. bytes in part-dup. packets */ 630 #define TCP_STAT_RCVOOPACK 39 /* out-of-order packets received */ 631 #define TCP_STAT_RCVOOBYTE 40 /* out-of-order bytes received */ 632 #define TCP_STAT_RCVPACKAFTERWIN 41 /* packets with data after window */ 633 #define TCP_STAT_RCVBYTEAFTERWIN 42 /* bytes received after window */ 634 #define TCP_STAT_RCVAFTERCLOSE 43 /* packets received after "close" */ 635 #define TCP_STAT_RCVWINPROBE 44 /* rcvd window probe packets */ 636 #define TCP_STAT_RCVDUPACK 45 /* rcvd duplicate ACKs */ 637 #define TCP_STAT_RCVACKTOOMUCH 46 /* rcvd ACKs for unsent data */ 638 #define TCP_STAT_RCVACKPACK 47 /* rcvd ACK packets */ 639 #define TCP_STAT_RCVACKBYTE 48 /* bytes ACKed by rcvd ACKs */ 640 #define TCP_STAT_RCVWINUPD 49 /* rcvd window update packets */ 641 #define TCP_STAT_PAWSDROP 50 /* segments dropped due to PAWS */ 642 #define TCP_STAT_PREDACK 51 /* times hdr predict OK for ACKs */ 643 #define TCP_STAT_PREDDAT 52 /* times hdr predict OK for data pkts */ 644 #define TCP_STAT_PCBHASHMISS 53 /* input packets missing PCB hash */ 645 #define TCP_STAT_NOPORT 54 /* no socket on port */ 646 #define TCP_STAT_BADSYN 55 /* received ACK for which we have 647 no SYN in compressed state */ 648 #define TCP_STAT_DELAYED_FREE 56 /* delayed pool_put() of tcpcb */ 649 #define TCP_STAT_SC_ADDED 57 /* # of sc entries added */ 650 #define TCP_STAT_SC_COMPLETED 58 /* # of sc connections completed */ 651 #define TCP_STAT_SC_TIMED_OUT 59 /* # of sc entries timed out */ 652 #define TCP_STAT_SC_OVERFLOWED 60 /* # of sc drops due to overflow */ 653 #define TCP_STAT_SC_RESET 61 /* # of sc drops due to RST */ 654 #define TCP_STAT_SC_UNREACH 62 /* # of sc drops due to ICMP unreach */ 655 #define TCP_STAT_SC_BUCKETOVERFLOW 63 /* # of sc drops due to bucket ovflow */ 656 #define TCP_STAT_SC_ABORTED 64 /* # of sc entries aborted (no mem) */ 657 #define TCP_STAT_SC_DUPESYN 65 /* # of duplicate SYNs received */ 658 #define TCP_STAT_SC_DROPPED 66 /* # of SYNs dropped (no route/mem) */ 659 #define TCP_STAT_SC_COLLISIONS 67 /* # of sc hash collisions */ 660 #define TCP_STAT_SC_RETRANSMITTED 68 /* # of sc retransmissions */ 661 #define TCP_STAT_SC_DELAYED_FREE 69 /* # of delayed pool_put()s */ 662 #define TCP_STAT_SELFQUENCH 70 /* # of ENOBUFS we get on output */ 663 #define TCP_STAT_BADSIG 71 /* # of drops due to bad signature */ 664 #define TCP_STAT_GOODSIG 72 /* # of packets with good signature */ 665 #define TCP_STAT_ECN_SHS 73 /* # of successful ECN handshakes */ 666 #define TCP_STAT_ECN_CE 74 /* # of packets with CE bit */ 667 #define TCP_STAT_ECN_ECT 75 /* # of packets with ECT(0) bit */ 668 669 #define TCP_NSTATS 76 670 671 /* 672 * Names for TCP sysctl objects. 673 */ 674 #define TCPCTL_RFC1323 1 /* RFC1323 timestamps/scaling */ 675 #define TCPCTL_SENDSPACE 2 /* default send buffer */ 676 #define TCPCTL_RECVSPACE 3 /* default recv buffer */ 677 #define TCPCTL_MSSDFLT 4 /* default seg size */ 678 #define TCPCTL_SYN_CACHE_LIMIT 5 /* max size of comp. state engine */ 679 #define TCPCTL_SYN_BUCKET_LIMIT 6 /* max size of hash bucket */ 680 #if 0 /*obsoleted*/ 681 #define TCPCTL_SYN_CACHE_INTER 7 /* interval of comp. state timer */ 682 #endif 683 #define TCPCTL_INIT_WIN 8 /* initial window */ 684 #define TCPCTL_MSS_IFMTU 9 /* mss from interface, not in_maxmtu */ 685 #define TCPCTL_SACK 10 /* RFC2018 selective acknowledgement */ 686 #define TCPCTL_WSCALE 11 /* RFC1323 window scaling */ 687 #define TCPCTL_TSTAMP 12 /* RFC1323 timestamps */ 688 #define TCPCTL_COMPAT_42 13 /* 4.2BSD TCP bug work-arounds */ 689 #define TCPCTL_CWM 14 /* Congestion Window Monitoring */ 690 #define TCPCTL_CWM_BURSTSIZE 15 /* burst size allowed by CWM */ 691 #define TCPCTL_ACK_ON_PUSH 16 /* ACK immediately on PUSH */ 692 #define TCPCTL_KEEPIDLE 17 /* keepalive idle time */ 693 #define TCPCTL_KEEPINTVL 18 /* keepalive probe interval */ 694 #define TCPCTL_KEEPCNT 19 /* keepalive count */ 695 #define TCPCTL_SLOWHZ 20 /* PR_SLOWHZ (read-only) */ 696 #define TCPCTL_NEWRENO 21 /* NewReno Congestion Control */ 697 #define TCPCTL_LOG_REFUSED 22 /* Log refused connections */ 698 #if 0 /*obsoleted*/ 699 #define TCPCTL_RSTRATELIMIT 23 /* RST rate limit */ 700 #endif 701 #define TCPCTL_RSTPPSLIMIT 24 /* RST pps limit */ 702 #define TCPCTL_DELACK_TICKS 25 /* # ticks to delay ACK */ 703 #define TCPCTL_INIT_WIN_LOCAL 26 /* initial window for local nets */ 704 #define TCPCTL_IDENT 27 /* rfc 931 identd */ 705 #define TCPCTL_ACKDROPRATELIMIT 28 /* SYN/RST -> ACK rate limit */ 706 #define TCPCTL_LOOPBACKCKSUM 29 /* do TCP checksum on loopback */ 707 #define TCPCTL_STATS 30 /* TCP statistics */ 708 #define TCPCTL_DEBUG 31 /* TCP debug sockets */ 709 #define TCPCTL_DEBX 32 /* # of tcp debug sockets */ 710 #define TCPCTL_DROP 33 /* drop tcp connection */ 711 #define TCPCTL_MSL 34 /* Max Segment Life */ 712 #define TCPCTL_MAXID 35 713 714 #define TCPCTL_NAMES { \ 715 { 0, 0 }, \ 716 { "rfc1323", CTLTYPE_INT }, \ 717 { "sendspace", CTLTYPE_INT }, \ 718 { "recvspace", CTLTYPE_INT }, \ 719 { "mssdflt", CTLTYPE_INT }, \ 720 { "syn_cache_limit", CTLTYPE_INT }, \ 721 { "syn_bucket_limit", CTLTYPE_INT }, \ 722 { 0, 0 },\ 723 { "init_win", CTLTYPE_INT }, \ 724 { "mss_ifmtu", CTLTYPE_INT }, \ 725 { "sack", CTLTYPE_INT }, \ 726 { "win_scale", CTLTYPE_INT }, \ 727 { "timestamps", CTLTYPE_INT }, \ 728 { "compat_42", CTLTYPE_INT }, \ 729 { "cwm", CTLTYPE_INT }, \ 730 { "cwm_burstsize", CTLTYPE_INT }, \ 731 { "ack_on_push", CTLTYPE_INT }, \ 732 { "keepidle", CTLTYPE_INT }, \ 733 { "keepintvl", CTLTYPE_INT }, \ 734 { "keepcnt", CTLTYPE_INT }, \ 735 { "slowhz", CTLTYPE_INT }, \ 736 { 0, 0 }, \ 737 { "log_refused",CTLTYPE_INT }, \ 738 { 0, 0 }, \ 739 { "rstppslimit", CTLTYPE_INT }, \ 740 { "delack_ticks", CTLTYPE_INT }, \ 741 { "init_win_local", CTLTYPE_INT }, \ 742 { "ident", CTLTYPE_STRUCT }, \ 743 { "ackdropppslimit", CTLTYPE_INT }, \ 744 { "do_loopback_cksum", CTLTYPE_INT }, \ 745 { "stats", CTLTYPE_STRUCT }, \ 746 { "debug", CTLTYPE_STRUCT }, \ 747 { "debx", CTLTYPE_INT }, \ 748 { "drop", CTLTYPE_STRUCT }, \ 749 { "msl", CTLTYPE_INT }, \ 750 } 751 752 #ifdef _KERNEL 753 extern struct inpcbtable tcbtable; /* head of queue of active tcpcb's */ 754 extern u_int32_t tcp_now; /* for RFC 1323 timestamps */ 755 extern int tcp_do_rfc1323; /* enabled/disabled? */ 756 extern int tcp_do_sack; /* SACK enabled/disabled? */ 757 extern int tcp_do_win_scale; /* RFC1323 window scaling enabled/disabled? */ 758 extern int tcp_do_timestamps; /* RFC1323 timestamps enabled/disabled? */ 759 extern int tcp_mssdflt; /* default seg size */ 760 extern int tcp_minmss; /* minimal seg size */ 761 extern int tcp_msl; /* max segment life */ 762 extern int tcp_init_win; /* initial window */ 763 extern int tcp_init_win_local; /* initial window for local nets */ 764 extern int tcp_mss_ifmtu; /* take MSS from interface, not in_maxmtu */ 765 extern int tcp_compat_42; /* work around ancient broken TCP peers */ 766 extern int tcp_cwm; /* enable Congestion Window Monitoring */ 767 extern int tcp_cwm_burstsize; /* burst size allowed by CWM */ 768 extern int tcp_ack_on_push; /* ACK immediately on PUSH */ 769 extern int tcp_syn_cache_limit; /* max entries for compressed state engine */ 770 extern int tcp_syn_bucket_limit;/* max entries per hash bucket */ 771 extern int tcp_log_refused; /* log refused connections */ 772 extern int tcp_do_ecn; /* TCP ECN enabled/disabled? */ 773 extern int tcp_ecn_maxretries; /* Max ECN setup retries */ 774 #if NRND > 0 775 extern int tcp_do_rfc1948; /* ISS by cryptographic hash */ 776 #endif 777 extern int tcp_sack_tp_maxholes; /* Max holes per connection. */ 778 extern int tcp_sack_globalmaxholes; /* Max holes per system. */ 779 extern int tcp_sack_globalholes; /* Number of holes present. */ 780 extern int tcp_do_abc; /* RFC3465 ABC enabled/disabled? */ 781 extern int tcp_abc_aggressive; /* 1: L=2*SMSS 0: L=1*SMSS */ 782 783 extern int tcp_rst_ppslim; 784 extern int tcp_ackdrop_ppslim; 785 786 extern int tcp_syn_cache_size; 787 extern struct syn_cache_head tcp_syn_cache[]; 788 extern u_long syn_cache_count; 789 790 #ifdef MBUFTRACE 791 extern struct mowner tcp_rx_mowner; 792 extern struct mowner tcp_tx_mowner; 793 extern struct mowner tcp_reass_mowner; 794 extern struct mowner tcp_sock_mowner; 795 extern struct mowner tcp_sock_rx_mowner; 796 extern struct mowner tcp_sock_tx_mowner; 797 extern struct mowner tcp_mowner; 798 #endif 799 800 extern int tcp_do_autorcvbuf; 801 extern int tcp_autorcvbuf_inc; 802 extern int tcp_autorcvbuf_max; 803 extern int tcp_do_autosndbuf; 804 extern int tcp_autosndbuf_inc; 805 extern int tcp_autosndbuf_max; 806 807 808 #define TCPCTL_VARIABLES { \ 809 { 0 }, \ 810 { 1, 0, &tcp_do_rfc1323 }, \ 811 { 1, 0, &tcp_sendspace }, \ 812 { 1, 0, &tcp_recvspace }, \ 813 { 1, 0, &tcp_mssdflt }, \ 814 { 1, 0, &tcp_syn_cache_limit }, \ 815 { 1, 0, &tcp_syn_bucket_limit }, \ 816 { 0 }, \ 817 { 1, 0, &tcp_init_win }, \ 818 { 1, 0, &tcp_mss_ifmtu }, \ 819 { 1, 0, &tcp_do_sack }, \ 820 { 1, 0, &tcp_do_win_scale }, \ 821 { 1, 0, &tcp_do_timestamps }, \ 822 { 1, 0, &tcp_compat_42 }, \ 823 { 1, 0, &tcp_cwm }, \ 824 { 1, 0, &tcp_cwm_burstsize }, \ 825 { 1, 0, &tcp_ack_on_push }, \ 826 { 1, 0, &tcp_keepidle }, \ 827 { 1, 0, &tcp_keepintvl }, \ 828 { 1, 0, &tcp_keepcnt }, \ 829 { 1, 1, 0, PR_SLOWHZ }, \ 830 { 0 }, \ 831 { 1, 0, &tcp_log_refused }, \ 832 { 0 }, \ 833 { 1, 0, &tcp_rst_ppslim }, \ 834 { 1, 0, &tcp_delack_ticks }, \ 835 { 1, 0, &tcp_init_win_local }, \ 836 { 1, 0, &tcp_ackdrop_ppslim }, \ 837 } 838 839 struct secasvar; 840 841 int tcp_attach(struct socket *); 842 void tcp_canceltimers(struct tcpcb *); 843 struct tcpcb * 844 tcp_close(struct tcpcb *); 845 int tcp_isdead(struct tcpcb *); 846 #ifdef INET6 847 void *tcp6_ctlinput(int, const struct sockaddr *, void *); 848 #endif 849 void *tcp_ctlinput(int, const struct sockaddr *, void *); 850 int tcp_ctloutput(int, struct socket *, struct sockopt *); 851 struct tcpcb * 852 tcp_disconnect(struct tcpcb *); 853 struct tcpcb * 854 tcp_drop(struct tcpcb *, int); 855 #ifdef TCP_SIGNATURE 856 int tcp_signature_apply(void *, void *, u_int); 857 struct secasvar *tcp_signature_getsav(struct mbuf *, struct tcphdr *); 858 int tcp_signature(struct mbuf *, struct tcphdr *, int, struct secasvar *, 859 char *); 860 #endif 861 void tcp_drain(void); 862 void tcp_established(struct tcpcb *); 863 void tcp_init(void); 864 #ifdef INET6 865 int tcp6_input(struct mbuf **, int *, int); 866 #endif 867 void tcp_input(struct mbuf *, ...); 868 u_int tcp_hdrsz(struct tcpcb *); 869 u_long tcp_mss_to_advertise(const struct ifnet *, int); 870 void tcp_mss_from_peer(struct tcpcb *, int); 871 void tcp_tcpcb_template(void); 872 struct tcpcb * 873 tcp_newtcpcb(int, void *); 874 void tcp_notify(struct inpcb *, int); 875 #ifdef INET6 876 void tcp6_notify(struct in6pcb *, int); 877 #endif 878 u_int tcp_optlen(struct tcpcb *); 879 int tcp_output(struct tcpcb *); 880 void tcp_pulloutofband(struct socket *, 881 struct tcphdr *, struct mbuf *, int); 882 void tcp_quench(struct inpcb *, int); 883 #ifdef INET6 884 void tcp6_quench(struct in6pcb *, int); 885 #endif 886 void tcp_mtudisc(struct inpcb *, int); 887 888 void tcpipqent_init(void); 889 struct ipqent *tcpipqent_alloc(void); 890 void tcpipqent_free(struct ipqent *); 891 892 int tcp_respond(struct tcpcb *, struct mbuf *, struct mbuf *, 893 struct tcphdr *, tcp_seq, tcp_seq, int); 894 void tcp_rmx_rtt(struct tcpcb *); 895 void tcp_setpersist(struct tcpcb *); 896 #ifdef TCP_SIGNATURE 897 int tcp_signature_compute(struct mbuf *, struct tcphdr *, int, int, 898 int, u_char *, u_int); 899 #endif 900 void tcp_slowtimo(void); 901 struct mbuf * 902 tcp_template(struct tcpcb *); 903 void tcp_trace(short, short, struct tcpcb *, struct mbuf *, int); 904 struct tcpcb * 905 tcp_usrclosed(struct tcpcb *); 906 void tcp_usrreq_init(void); 907 int tcp_usrreq(struct socket *, 908 int, struct mbuf *, struct mbuf *, struct mbuf *, struct lwp *); 909 void tcp_xmit_timer(struct tcpcb *, uint32_t); 910 tcp_seq tcp_new_iss(struct tcpcb *, tcp_seq); 911 tcp_seq tcp_new_iss1(void *, void *, u_int16_t, u_int16_t, size_t, 912 tcp_seq); 913 914 void tcp_sack_init(void); 915 void tcp_new_dsack(struct tcpcb *, tcp_seq, u_int32_t); 916 void tcp_sack_option(struct tcpcb *, const struct tcphdr *, 917 const u_char *, int); 918 void tcp_del_sackholes(struct tcpcb *, const struct tcphdr *); 919 void tcp_free_sackholes(struct tcpcb *); 920 void tcp_sack_adjust(struct tcpcb *tp); 921 struct sackhole *tcp_sack_output(struct tcpcb *tp, int *sack_bytes_rexmt); 922 void tcp_sack_newack(struct tcpcb *, const struct tcphdr *); 923 int tcp_sack_numblks(const struct tcpcb *); 924 #define TCP_SACK_OPTLEN(nblks) ((nblks) * 8 + 2 + 2) 925 926 void tcp_statinc(u_int); 927 void tcp_statadd(u_int, uint64_t); 928 929 int syn_cache_add(struct sockaddr *, struct sockaddr *, 930 struct tcphdr *, unsigned int, struct socket *, 931 struct mbuf *, u_char *, int, struct tcp_opt_info *); 932 void syn_cache_unreach(const struct sockaddr *, const struct sockaddr *, 933 struct tcphdr *); 934 struct socket *syn_cache_get(struct sockaddr *, struct sockaddr *, 935 struct tcphdr *, unsigned int, unsigned int, 936 struct socket *so, struct mbuf *); 937 void syn_cache_init(void); 938 void syn_cache_insert(struct syn_cache *, struct tcpcb *); 939 struct syn_cache *syn_cache_lookup(const struct sockaddr *, const struct sockaddr *, 940 struct syn_cache_head **); 941 void syn_cache_reset(struct sockaddr *, struct sockaddr *, 942 struct tcphdr *); 943 int syn_cache_respond(struct syn_cache *, struct mbuf *); 944 void syn_cache_timer(void *); 945 void syn_cache_cleanup(struct tcpcb *); 946 947 int tcp_input_checksum(int, struct mbuf *, const struct tcphdr *, int, int, 948 int); 949 #endif 950 951 #endif /* !_NETINET_TCP_VAR_H_ */ 952
Indexes created Fri Sep 26 08:10:20 GMT 2025