1 /* $NetBSD: tcp_var.h,v 1.164 2011/04/20 13:35:52 gdt 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 * See RFC2988 for a discussion of RTO calculation; comments assume 550 * familiarity with that document. 551 * 552 * The smoothed round-trip time and estimated variance are stored as 553 * fixed point numbers. Historically, srtt was scaled by 554 * TCP_RTT_SHIFT bits, and rttvar by TCP_RTTVAR_SHIFT bits. Because 555 * the values coincide with the alpha and beta parameters suggested 556 * for RTO calculation (1/8 for srtt, 1/4 for rttvar), the combination 557 * of computing 1/8 of the new value and transforming it to the 558 * fixed-point representation required zero instructions. However, 559 * the storage representations no longer coincide with the alpha/beta 560 * shifts; instead, more fractional bits are present. 561 * 562 * The storage representation of srtt is 1/32 slow ticks, or 1/64 s. 563 * (The assumption that a slow tick is 500 ms should not be present in 564 * the code.) 565 * 566 * The storage representation of rttvar is 1/16 slow ticks, or 1/32 s. 567 * There may be some confusion about this in the code. 568 * 569 * For historical reasons, these scales are also used in smoothing the 570 * average (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed). 571 * This results in alpha of 0.125 and beta of 0.25, following RFC2988 572 * section 2.3 573 */ 574 #define TCP_RTT_SHIFT 3 /* shift for srtt; 3 bits frac. */ 575 #define TCP_RTTVAR_SHIFT 2 /* multiplier for rttvar; 2 bits */ 576 577 /* 578 * Compute TCP retransmission timer, following RFC2988. 579 * This macro returns a value in slow timeout ticks. 580 * 581 * Section 2.2 requires that the RTO value be 582 * srtt + max(G, 4*RTTVAR) 583 * where G is the clock granularity. 584 * 585 * This comment has not necessarily been updated for the new storage 586 * representation: 587 * 588 * Because of the way we do the smoothing, srtt and rttvar 589 * will each average +1/2 tick of bias. When we compute 590 * the retransmit timer, we want 1/2 tick of rounding and 591 * 1 extra tick because of +-1/2 tick uncertainty in the 592 * firing of the timer. The bias will give us exactly the 593 * 1.5 tick we need. But, because the bias is 594 * statistical, we have to test that we don't drop below 595 * the minimum feasible timer (which is 2 ticks). 596 * This macro assumes that the value of 1<<TCP_RTTVAR_SHIFT 597 * is the same as the multiplier for rttvar. 598 * 599 * This macro appears to be wrong; it should be checking rttvar*4 in 600 * ticks and making sure we use 1 instead if rttvar*4 rounds to 0. It 601 * appears to be treating srtt as being in the old storage 602 * representation, resulting in a factor of 4 extra. 603 */ 604 #define TCP_REXMTVAL(tp) \ 605 ((((tp)->t_srtt >> TCP_RTT_SHIFT) + (tp)->t_rttvar) >> 2) 606 607 /* 608 * Compute the initial window for slow start. 609 */ 610 #define TCP_INITIAL_WINDOW(iw, segsz) \ 611 (((iw) == 0) ? (min(4 * (segsz), max(2 * (segsz), 4380))) : \ 612 ((segsz) * (iw))) 613 614 /* 615 * TCP statistics. 616 * Each counter is an unsigned 64-bit value. 617 * 618 * Many of these should be kept per connection, but that's inconvenient 619 * at the moment. 620 */ 621 #define TCP_STAT_CONNATTEMPT 0 /* connections initiated */ 622 #define TCP_STAT_ACCEPTS 1 /* connections accepted */ 623 #define TCP_STAT_CONNECTS 2 /* connections established */ 624 #define TCP_STAT_DROPS 3 /* connections dropped */ 625 #define TCP_STAT_CONNDROPS 4 /* embryonic connections dropped */ 626 #define TCP_STAT_CLOSED 5 /* conn. closed (includes drops) */ 627 #define TCP_STAT_SEGSTIMED 6 /* segs where we tried to get rtt */ 628 #define TCP_STAT_RTTUPDATED 7 /* times we succeeded */ 629 #define TCP_STAT_DELACK 8 /* delayed ACKs sent */ 630 #define TCP_STAT_TIMEOUTDROP 9 /* conn. dropped in rxmt timeout */ 631 #define TCP_STAT_REXMTTIMEO 10 /* retransmit timeouts */ 632 #define TCP_STAT_PERSISTTIMEO 11 /* persist timeouts */ 633 #define TCP_STAT_KEEPTIMEO 12 /* keepalive timeouts */ 634 #define TCP_STAT_KEEPPROBE 13 /* keepalive probes sent */ 635 #define TCP_STAT_KEEPDROPS 14 /* connections dropped in keepalive */ 636 #define TCP_STAT_PERSISTDROPS 15 /* connections dropped in persist */ 637 #define TCP_STAT_CONNSDRAINED 16 /* connections drained due to memory 638 shortage */ 639 #define TCP_STAT_PMTUBLACKHOLE 17 /* PMTUD blackhole detected */ 640 #define TCP_STAT_SNDTOTAL 18 /* total packets sent */ 641 #define TCP_STAT_SNDPACK 19 /* data packlets sent */ 642 #define TCP_STAT_SNDBYTE 20 /* data bytes sent */ 643 #define TCP_STAT_SNDREXMITPACK 21 /* data packets retransmitted */ 644 #define TCP_STAT_SNDREXMITBYTE 22 /* data bytes retransmitted */ 645 #define TCP_STAT_SNDACKS 23 /* ACK-only packets sent */ 646 #define TCP_STAT_SNDPROBE 24 /* window probes sent */ 647 #define TCP_STAT_SNDURG 25 /* packets sent with URG only */ 648 #define TCP_STAT_SNDWINUP 26 /* window update-only packets sent */ 649 #define TCP_STAT_SNDCTRL 27 /* control (SYN|FIN|RST) packets sent */ 650 #define TCP_STAT_RCVTOTAL 28 /* total packets received */ 651 #define TCP_STAT_RCVPACK 29 /* packets received in sequence */ 652 #define TCP_STAT_RCVBYTE 30 /* bytes received in sequence */ 653 #define TCP_STAT_RCVBADSUM 31 /* packets received with cksum errs */ 654 #define TCP_STAT_RCVBADOFF 32 /* packets received with bad offset */ 655 #define TCP_STAT_RCVMEMDROP 33 /* packets dropped for lack of memory */ 656 #define TCP_STAT_RCVSHORT 34 /* packets received too short */ 657 #define TCP_STAT_RCVDUPPACK 35 /* duplicate-only packets received */ 658 #define TCP_STAT_RCVDUPBYTE 36 /* duplicate-only bytes received */ 659 #define TCP_STAT_RCVPARTDUPPACK 37 /* packets with some duplicate data */ 660 #define TCP_STAT_RCVPARTDUPBYTE 38 /* dup. bytes in part-dup. packets */ 661 #define TCP_STAT_RCVOOPACK 39 /* out-of-order packets received */ 662 #define TCP_STAT_RCVOOBYTE 40 /* out-of-order bytes received */ 663 #define TCP_STAT_RCVPACKAFTERWIN 41 /* packets with data after window */ 664 #define TCP_STAT_RCVBYTEAFTERWIN 42 /* bytes received after window */ 665 #define TCP_STAT_RCVAFTERCLOSE 43 /* packets received after "close" */ 666 #define TCP_STAT_RCVWINPROBE 44 /* rcvd window probe packets */ 667 #define TCP_STAT_RCVDUPACK 45 /* rcvd duplicate ACKs */ 668 #define TCP_STAT_RCVACKTOOMUCH 46 /* rcvd ACKs for unsent data */ 669 #define TCP_STAT_RCVACKPACK 47 /* rcvd ACK packets */ 670 #define TCP_STAT_RCVACKBYTE 48 /* bytes ACKed by rcvd ACKs */ 671 #define TCP_STAT_RCVWINUPD 49 /* rcvd window update packets */ 672 #define TCP_STAT_PAWSDROP 50 /* segments dropped due to PAWS */ 673 #define TCP_STAT_PREDACK 51 /* times hdr predict OK for ACKs */ 674 #define TCP_STAT_PREDDAT 52 /* times hdr predict OK for data pkts */ 675 #define TCP_STAT_PCBHASHMISS 53 /* input packets missing PCB hash */ 676 #define TCP_STAT_NOPORT 54 /* no socket on port */ 677 #define TCP_STAT_BADSYN 55 /* received ACK for which we have 678 no SYN in compressed state */ 679 #define TCP_STAT_DELAYED_FREE 56 /* delayed pool_put() of tcpcb */ 680 #define TCP_STAT_SC_ADDED 57 /* # of sc entries added */ 681 #define TCP_STAT_SC_COMPLETED 58 /* # of sc connections completed */ 682 #define TCP_STAT_SC_TIMED_OUT 59 /* # of sc entries timed out */ 683 #define TCP_STAT_SC_OVERFLOWED 60 /* # of sc drops due to overflow */ 684 #define TCP_STAT_SC_RESET 61 /* # of sc drops due to RST */ 685 #define TCP_STAT_SC_UNREACH 62 /* # of sc drops due to ICMP unreach */ 686 #define TCP_STAT_SC_BUCKETOVERFLOW 63 /* # of sc drops due to bucket ovflow */ 687 #define TCP_STAT_SC_ABORTED 64 /* # of sc entries aborted (no mem) */ 688 #define TCP_STAT_SC_DUPESYN 65 /* # of duplicate SYNs received */ 689 #define TCP_STAT_SC_DROPPED 66 /* # of SYNs dropped (no route/mem) */ 690 #define TCP_STAT_SC_COLLISIONS 67 /* # of sc hash collisions */ 691 #define TCP_STAT_SC_RETRANSMITTED 68 /* # of sc retransmissions */ 692 #define TCP_STAT_SC_DELAYED_FREE 69 /* # of delayed pool_put()s */ 693 #define TCP_STAT_SELFQUENCH 70 /* # of ENOBUFS we get on output */ 694 #define TCP_STAT_BADSIG 71 /* # of drops due to bad signature */ 695 #define TCP_STAT_GOODSIG 72 /* # of packets with good signature */ 696 #define TCP_STAT_ECN_SHS 73 /* # of successful ECN handshakes */ 697 #define TCP_STAT_ECN_CE 74 /* # of packets with CE bit */ 698 #define TCP_STAT_ECN_ECT 75 /* # of packets with ECT(0) bit */ 699 700 #define TCP_NSTATS 76 701 702 /* 703 * Names for TCP sysctl objects. 704 */ 705 #define TCPCTL_RFC1323 1 /* RFC1323 timestamps/scaling */ 706 #define TCPCTL_SENDSPACE 2 /* default send buffer */ 707 #define TCPCTL_RECVSPACE 3 /* default recv buffer */ 708 #define TCPCTL_MSSDFLT 4 /* default seg size */ 709 #define TCPCTL_SYN_CACHE_LIMIT 5 /* max size of comp. state engine */ 710 #define TCPCTL_SYN_BUCKET_LIMIT 6 /* max size of hash bucket */ 711 #if 0 /*obsoleted*/ 712 #define TCPCTL_SYN_CACHE_INTER 7 /* interval of comp. state timer */ 713 #endif 714 #define TCPCTL_INIT_WIN 8 /* initial window */ 715 #define TCPCTL_MSS_IFMTU 9 /* mss from interface, not in_maxmtu */ 716 #define TCPCTL_SACK 10 /* RFC2018 selective acknowledgement */ 717 #define TCPCTL_WSCALE 11 /* RFC1323 window scaling */ 718 #define TCPCTL_TSTAMP 12 /* RFC1323 timestamps */ 719 #define TCPCTL_COMPAT_42 13 /* 4.2BSD TCP bug work-arounds */ 720 #define TCPCTL_CWM 14 /* Congestion Window Monitoring */ 721 #define TCPCTL_CWM_BURSTSIZE 15 /* burst size allowed by CWM */ 722 #define TCPCTL_ACK_ON_PUSH 16 /* ACK immediately on PUSH */ 723 #define TCPCTL_KEEPIDLE 17 /* keepalive idle time */ 724 #define TCPCTL_KEEPINTVL 18 /* keepalive probe interval */ 725 #define TCPCTL_KEEPCNT 19 /* keepalive count */ 726 #define TCPCTL_SLOWHZ 20 /* PR_SLOWHZ (read-only) */ 727 #define TCPCTL_NEWRENO 21 /* NewReno Congestion Control */ 728 #define TCPCTL_LOG_REFUSED 22 /* Log refused connections */ 729 #if 0 /*obsoleted*/ 730 #define TCPCTL_RSTRATELIMIT 23 /* RST rate limit */ 731 #endif 732 #define TCPCTL_RSTPPSLIMIT 24 /* RST pps limit */ 733 #define TCPCTL_DELACK_TICKS 25 /* # ticks to delay ACK */ 734 #define TCPCTL_INIT_WIN_LOCAL 26 /* initial window for local nets */ 735 #define TCPCTL_IDENT 27 /* rfc 931 identd */ 736 #define TCPCTL_ACKDROPRATELIMIT 28 /* SYN/RST -> ACK rate limit */ 737 #define TCPCTL_LOOPBACKCKSUM 29 /* do TCP checksum on loopback */ 738 #define TCPCTL_STATS 30 /* TCP statistics */ 739 #define TCPCTL_DEBUG 31 /* TCP debug sockets */ 740 #define TCPCTL_DEBX 32 /* # of tcp debug sockets */ 741 #define TCPCTL_DROP 33 /* drop tcp connection */ 742 #define TCPCTL_MSL 34 /* Max Segment Life */ 743 #define TCPCTL_MAXID 35 744 745 #define TCPCTL_NAMES { \ 746 { 0, 0 }, \ 747 { "rfc1323", CTLTYPE_INT }, \ 748 { "sendspace", CTLTYPE_INT }, \ 749 { "recvspace", CTLTYPE_INT }, \ 750 { "mssdflt", CTLTYPE_INT }, \ 751 { "syn_cache_limit", CTLTYPE_INT }, \ 752 { "syn_bucket_limit", CTLTYPE_INT }, \ 753 { 0, 0 },\ 754 { "init_win", CTLTYPE_INT }, \ 755 { "mss_ifmtu", CTLTYPE_INT }, \ 756 { "sack", CTLTYPE_INT }, \ 757 { "win_scale", CTLTYPE_INT }, \ 758 { "timestamps", CTLTYPE_INT }, \ 759 { "compat_42", CTLTYPE_INT }, \ 760 { "cwm", CTLTYPE_INT }, \ 761 { "cwm_burstsize", CTLTYPE_INT }, \ 762 { "ack_on_push", CTLTYPE_INT }, \ 763 { "keepidle", CTLTYPE_INT }, \ 764 { "keepintvl", CTLTYPE_INT }, \ 765 { "keepcnt", CTLTYPE_INT }, \ 766 { "slowhz", CTLTYPE_INT }, \ 767 { 0, 0 }, \ 768 { "log_refused",CTLTYPE_INT }, \ 769 { 0, 0 }, \ 770 { "rstppslimit", CTLTYPE_INT }, \ 771 { "delack_ticks", CTLTYPE_INT }, \ 772 { "init_win_local", CTLTYPE_INT }, \ 773 { "ident", CTLTYPE_STRUCT }, \ 774 { "ackdropppslimit", CTLTYPE_INT }, \ 775 { "do_loopback_cksum", CTLTYPE_INT }, \ 776 { "stats", CTLTYPE_STRUCT }, \ 777 { "debug", CTLTYPE_STRUCT }, \ 778 { "debx", CTLTYPE_INT }, \ 779 { "drop", CTLTYPE_STRUCT }, \ 780 { "msl", CTLTYPE_INT }, \ 781 } 782 783 #ifdef _KERNEL 784 extern struct inpcbtable tcbtable; /* head of queue of active tcpcb's */ 785 extern u_int32_t tcp_now; /* for RFC 1323 timestamps */ 786 extern int tcp_do_rfc1323; /* enabled/disabled? */ 787 extern int tcp_do_sack; /* SACK enabled/disabled? */ 788 extern int tcp_do_win_scale; /* RFC1323 window scaling enabled/disabled? */ 789 extern int tcp_do_timestamps; /* RFC1323 timestamps enabled/disabled? */ 790 extern int tcp_mssdflt; /* default seg size */ 791 extern int tcp_minmss; /* minimal seg size */ 792 extern int tcp_msl; /* max segment life */ 793 extern int tcp_init_win; /* initial window */ 794 extern int tcp_init_win_local; /* initial window for local nets */ 795 extern int tcp_mss_ifmtu; /* take MSS from interface, not in_maxmtu */ 796 extern int tcp_compat_42; /* work around ancient broken TCP peers */ 797 extern int tcp_cwm; /* enable Congestion Window Monitoring */ 798 extern int tcp_cwm_burstsize; /* burst size allowed by CWM */ 799 extern int tcp_ack_on_push; /* ACK immediately on PUSH */ 800 extern int tcp_syn_cache_limit; /* max entries for compressed state engine */ 801 extern int tcp_syn_bucket_limit;/* max entries per hash bucket */ 802 extern int tcp_log_refused; /* log refused connections */ 803 extern int tcp_do_ecn; /* TCP ECN enabled/disabled? */ 804 extern int tcp_ecn_maxretries; /* Max ECN setup retries */ 805 #if NRND > 0 806 extern int tcp_do_rfc1948; /* ISS by cryptographic hash */ 807 #endif 808 extern int tcp_sack_tp_maxholes; /* Max holes per connection. */ 809 extern int tcp_sack_globalmaxholes; /* Max holes per system. */ 810 extern int tcp_sack_globalholes; /* Number of holes present. */ 811 extern int tcp_do_abc; /* RFC3465 ABC enabled/disabled? */ 812 extern int tcp_abc_aggressive; /* 1: L=2*SMSS 0: L=1*SMSS */ 813 814 extern int tcp_rst_ppslim; 815 extern int tcp_ackdrop_ppslim; 816 817 extern int tcp_syn_cache_size; 818 extern struct syn_cache_head tcp_syn_cache[]; 819 extern u_long syn_cache_count; 820 821 #ifdef MBUFTRACE 822 extern struct mowner tcp_rx_mowner; 823 extern struct mowner tcp_tx_mowner; 824 extern struct mowner tcp_reass_mowner; 825 extern struct mowner tcp_sock_mowner; 826 extern struct mowner tcp_sock_rx_mowner; 827 extern struct mowner tcp_sock_tx_mowner; 828 extern struct mowner tcp_mowner; 829 #endif 830 831 extern int tcp_do_autorcvbuf; 832 extern int tcp_autorcvbuf_inc; 833 extern int tcp_autorcvbuf_max; 834 extern int tcp_do_autosndbuf; 835 extern int tcp_autosndbuf_inc; 836 extern int tcp_autosndbuf_max; 837 838 839 #define TCPCTL_VARIABLES { \ 840 { 0 }, \ 841 { 1, 0, &tcp_do_rfc1323 }, \ 842 { 1, 0, &tcp_sendspace }, \ 843 { 1, 0, &tcp_recvspace }, \ 844 { 1, 0, &tcp_mssdflt }, \ 845 { 1, 0, &tcp_syn_cache_limit }, \ 846 { 1, 0, &tcp_syn_bucket_limit }, \ 847 { 0 }, \ 848 { 1, 0, &tcp_init_win }, \ 849 { 1, 0, &tcp_mss_ifmtu }, \ 850 { 1, 0, &tcp_do_sack }, \ 851 { 1, 0, &tcp_do_win_scale }, \ 852 { 1, 0, &tcp_do_timestamps }, \ 853 { 1, 0, &tcp_compat_42 }, \ 854 { 1, 0, &tcp_cwm }, \ 855 { 1, 0, &tcp_cwm_burstsize }, \ 856 { 1, 0, &tcp_ack_on_push }, \ 857 { 1, 0, &tcp_keepidle }, \ 858 { 1, 0, &tcp_keepintvl }, \ 859 { 1, 0, &tcp_keepcnt }, \ 860 { 1, 1, 0, PR_SLOWHZ }, \ 861 { 0 }, \ 862 { 1, 0, &tcp_log_refused }, \ 863 { 0 }, \ 864 { 1, 0, &tcp_rst_ppslim }, \ 865 { 1, 0, &tcp_delack_ticks }, \ 866 { 1, 0, &tcp_init_win_local }, \ 867 { 1, 0, &tcp_ackdrop_ppslim }, \ 868 } 869 870 struct secasvar; 871 872 int tcp_attach(struct socket *); 873 void tcp_canceltimers(struct tcpcb *); 874 struct tcpcb * 875 tcp_close(struct tcpcb *); 876 int tcp_isdead(struct tcpcb *); 877 #ifdef INET6 878 void *tcp6_ctlinput(int, const struct sockaddr *, void *); 879 #endif 880 void *tcp_ctlinput(int, const struct sockaddr *, void *); 881 int tcp_ctloutput(int, struct socket *, struct sockopt *); 882 struct tcpcb * 883 tcp_disconnect(struct tcpcb *); 884 struct tcpcb * 885 tcp_drop(struct tcpcb *, int); 886 #ifdef TCP_SIGNATURE 887 int tcp_signature_apply(void *, void *, u_int); 888 struct secasvar *tcp_signature_getsav(struct mbuf *, struct tcphdr *); 889 int tcp_signature(struct mbuf *, struct tcphdr *, int, struct secasvar *, 890 char *); 891 #endif 892 void tcp_drain(void); 893 void tcp_established(struct tcpcb *); 894 void tcp_init(void); 895 #ifdef INET6 896 int tcp6_input(struct mbuf **, int *, int); 897 #endif 898 void tcp_input(struct mbuf *, ...); 899 u_int tcp_hdrsz(struct tcpcb *); 900 u_long tcp_mss_to_advertise(const struct ifnet *, int); 901 void tcp_mss_from_peer(struct tcpcb *, int); 902 void tcp_tcpcb_template(void); 903 struct tcpcb * 904 tcp_newtcpcb(int, void *); 905 void tcp_notify(struct inpcb *, int); 906 #ifdef INET6 907 void tcp6_notify(struct in6pcb *, int); 908 #endif 909 u_int tcp_optlen(struct tcpcb *); 910 int tcp_output(struct tcpcb *); 911 void tcp_pulloutofband(struct socket *, 912 struct tcphdr *, struct mbuf *, int); 913 void tcp_quench(struct inpcb *, int); 914 #ifdef INET6 915 void tcp6_quench(struct in6pcb *, int); 916 #endif 917 void tcp_mtudisc(struct inpcb *, int); 918 919 void tcpipqent_init(void); 920 struct ipqent *tcpipqent_alloc(void); 921 void tcpipqent_free(struct ipqent *); 922 923 int tcp_respond(struct tcpcb *, struct mbuf *, struct mbuf *, 924 struct tcphdr *, tcp_seq, tcp_seq, int); 925 void tcp_rmx_rtt(struct tcpcb *); 926 void tcp_setpersist(struct tcpcb *); 927 #ifdef TCP_SIGNATURE 928 int tcp_signature_compute(struct mbuf *, struct tcphdr *, int, int, 929 int, u_char *, u_int); 930 #endif 931 void tcp_slowtimo(void); 932 struct mbuf * 933 tcp_template(struct tcpcb *); 934 void tcp_trace(short, short, struct tcpcb *, struct mbuf *, int); 935 struct tcpcb * 936 tcp_usrclosed(struct tcpcb *); 937 void tcp_usrreq_init(void); 938 int tcp_usrreq(struct socket *, 939 int, struct mbuf *, struct mbuf *, struct mbuf *, struct lwp *); 940 void tcp_xmit_timer(struct tcpcb *, uint32_t); 941 tcp_seq tcp_new_iss(struct tcpcb *, tcp_seq); 942 tcp_seq tcp_new_iss1(void *, void *, u_int16_t, u_int16_t, size_t, 943 tcp_seq); 944 945 void tcp_sack_init(void); 946 void tcp_new_dsack(struct tcpcb *, tcp_seq, u_int32_t); 947 void tcp_sack_option(struct tcpcb *, const struct tcphdr *, 948 const u_char *, int); 949 void tcp_del_sackholes(struct tcpcb *, const struct tcphdr *); 950 void tcp_free_sackholes(struct tcpcb *); 951 void tcp_sack_adjust(struct tcpcb *tp); 952 struct sackhole *tcp_sack_output(struct tcpcb *tp, int *sack_bytes_rexmt); 953 void tcp_sack_newack(struct tcpcb *, const struct tcphdr *); 954 int tcp_sack_numblks(const struct tcpcb *); 955 #define TCP_SACK_OPTLEN(nblks) ((nblks) * 8 + 2 + 2) 956 957 void tcp_statinc(u_int); 958 void tcp_statadd(u_int, uint64_t); 959 960 int syn_cache_add(struct sockaddr *, struct sockaddr *, 961 struct tcphdr *, unsigned int, struct socket *, 962 struct mbuf *, u_char *, int, struct tcp_opt_info *); 963 void syn_cache_unreach(const struct sockaddr *, const struct sockaddr *, 964 struct tcphdr *); 965 struct socket *syn_cache_get(struct sockaddr *, struct sockaddr *, 966 struct tcphdr *, unsigned int, unsigned int, 967 struct socket *so, struct mbuf *); 968 void syn_cache_init(void); 969 void syn_cache_insert(struct syn_cache *, struct tcpcb *); 970 struct syn_cache *syn_cache_lookup(const struct sockaddr *, const struct sockaddr *, 971 struct syn_cache_head **); 972 void syn_cache_reset(struct sockaddr *, struct sockaddr *, 973 struct tcphdr *); 974 int syn_cache_respond(struct syn_cache *, struct mbuf *); 975 void syn_cache_timer(void *); 976 void syn_cache_cleanup(struct tcpcb *); 977 978 int tcp_input_checksum(int, struct mbuf *, const struct tcphdr *, int, int, 979 int); 980 #endif 981 982 #endif /* !_NETINET_TCP_VAR_H_ */ 983