tcp_var.h revision 1.158
1 /* $NetBSD: tcp_var.h,v 1.158 2008/08/06 15:01:23 plunky 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 short t_partialacks; /* partials acks during fast rexmit */ 195 u_short t_peermss; /* peer's maximum segment size */ 196 u_short t_ourmss; /* our's maximum segment size */ 197 u_short t_segsz; /* current segment size in use */ 198 char t_force; /* 1 if forcing out a byte */ 199 u_int t_flags; 200 #define TF_ACKNOW 0x0001 /* ack peer immediately */ 201 #define TF_DELACK 0x0002 /* ack, but try to delay it */ 202 #define TF_NODELAY 0x0004 /* don't delay packets to coalesce */ 203 #define TF_NOOPT 0x0008 /* don't use tcp options */ 204 #define TF_REQ_SCALE 0x0020 /* have/will request window scaling */ 205 #define TF_RCVD_SCALE 0x0040 /* other side has requested scaling */ 206 #define TF_REQ_TSTMP 0x0080 /* have/will request timestamps */ 207 #define TF_RCVD_TSTMP 0x0100 /* a timestamp was received in SYN */ 208 #define TF_SACK_PERMIT 0x0200 /* other side said I could SACK */ 209 #define TF_SYN_REXMT 0x0400 /* rexmit timer fired on SYN */ 210 #define TF_WILL_SACK 0x0800 /* try to use SACK */ 211 #define TF_REASSEMBLING 0x1000 /* we're busy reassembling */ 212 #define TF_DEAD 0x2000 /* dead and to-be-released */ 213 #define TF_PMTUD_PEND 0x4000 /* Path MTU Discovery pending */ 214 #define TF_ECN_PERMIT 0x10000 /* other side said is ECN-ready */ 215 #define TF_ECN_SND_CWR 0x20000 /* ECN CWR in queue */ 216 #define TF_ECN_SND_ECE 0x40000 /* ECN ECE in queue */ 217 #define TF_SIGNATURE 0x400000 /* require MD5 digests (RFC2385) */ 218 219 220 struct mbuf *t_template; /* skeletal packet for transmit */ 221 struct inpcb *t_inpcb; /* back pointer to internet pcb */ 222 struct in6pcb *t_in6pcb; /* back pointer to internet pcb */ 223 callout_t t_delack_ch; /* delayed ACK callout */ 224 /* 225 * The following fields are used as in the protocol specification. 226 * See RFC793, Dec. 1981, page 21. 227 */ 228 /* send sequence variables */ 229 tcp_seq snd_una; /* send unacknowledged */ 230 tcp_seq snd_nxt; /* send next */ 231 tcp_seq snd_up; /* send urgent pointer */ 232 tcp_seq snd_wl1; /* window update seg seq number */ 233 tcp_seq snd_wl2; /* window update seg ack number */ 234 tcp_seq iss; /* initial send sequence number */ 235 u_long snd_wnd; /* send window */ 236 tcp_seq snd_recover; /* for use in fast recovery */ 237 tcp_seq snd_high; /* NewReno false fast rexmit seq */ 238 /* receive sequence variables */ 239 u_long rcv_wnd; /* receive window */ 240 tcp_seq rcv_nxt; /* receive next */ 241 tcp_seq rcv_up; /* receive urgent pointer */ 242 tcp_seq irs; /* initial receive sequence number */ 243 /* 244 * Additional variables for this implementation. 245 */ 246 /* receive variables */ 247 tcp_seq rcv_adv; /* advertised window */ 248 /* retransmit variables */ 249 tcp_seq snd_max; /* highest sequence number sent; 250 * used to recognize retransmits 251 */ 252 /* congestion control (for slow start, source quench, retransmit after loss) */ 253 u_long snd_cwnd; /* congestion-controlled window */ 254 u_long snd_ssthresh; /* snd_cwnd size threshhold for 255 * for slow start exponential to 256 * linear switch 257 */ 258 /* auto-sizing variables */ 259 u_int rfbuf_cnt; /* recv buffer autoscaling byte count */ 260 uint32_t rfbuf_ts; /* recv buffer autoscaling timestamp */ 261 262 /* 263 * transmit timing stuff. See below for scale of srtt and rttvar. 264 * "Variance" is actually smoothed difference. 265 */ 266 uint32_t t_rcvtime; /* time last segment received */ 267 uint32_t t_rtttime; /* time we started measuring rtt */ 268 tcp_seq t_rtseq; /* sequence number being timed */ 269 int32_t t_srtt; /* smoothed round-trip time */ 270 int32_t t_rttvar; /* variance in round-trip time */ 271 uint32_t t_rttmin; /* minimum rtt allowed */ 272 u_long max_sndwnd; /* largest window peer has offered */ 273 274 /* out-of-band data */ 275 char t_oobflags; /* have some */ 276 char t_iobc; /* input character */ 277 #define TCPOOB_HAVEDATA 0x01 278 #define TCPOOB_HADDATA 0x02 279 short t_softerror; /* possible error not yet reported */ 280 281 /* RFC 1323 variables */ 282 u_char snd_scale; /* window scaling for send window */ 283 u_char rcv_scale; /* window scaling for recv window */ 284 u_char request_r_scale; /* pending window scaling */ 285 u_char requested_s_scale; 286 u_int32_t ts_recent; /* timestamp echo data */ 287 u_int32_t ts_recent_age; /* when last updated */ 288 u_int32_t ts_timebase; /* our timebase */ 289 tcp_seq last_ack_sent; 290 291 /* RFC 3465 variables */ 292 u_long t_bytes_acked; /* ABC "bytes_acked" parameter */ 293 294 /* SACK stuff */ 295 #define TCP_SACK_MAX 3 296 #define TCPSACK_NONE 0 297 #define TCPSACK_HAVED 1 298 u_char rcv_sack_flags; /* SACK flags. */ 299 struct sackblk rcv_dsack_block; /* RX D-SACK block. */ 300 struct ipqehead timeq; /* time sequenced queue. */ 301 struct sackhead snd_holes; /* TX SACK holes. */ 302 int snd_numholes; /* Number of TX SACK holes. */ 303 tcp_seq rcv_lastsack; /* last seq number(+1) sack'd by rcv'r*/ 304 tcp_seq sack_newdata; /* New data xmitted in this recovery 305 episode starts at this seq number*/ 306 tcp_seq snd_fack; /* FACK TCP. Forward-most data held by 307 peer. */ 308 309 /* pointer for syn cache entries*/ 310 LIST_HEAD(, syn_cache) t_sc; /* list of entries by this tcb */ 311 312 /* prediction of next mbuf when using large window sizes */ 313 struct mbuf *t_lastm; /* last mbuf that data was sent from */ 314 int t_inoff; /* data offset in previous mbuf */ 315 int t_lastoff; /* last data address in mbuf chain */ 316 int t_lastlen; /* last length read from mbuf chain */ 317 318 /* Path-MTU discovery blackhole detection */ 319 int t_mtudisc; /* perform mtudisc for this tcb */ 320 /* Path-MTU Discovery Information */ 321 u_int t_pmtud_mss_acked; /* MSS acked, lower bound for MTU */ 322 u_int t_pmtud_mtu_sent; /* MTU used, upper bound for MTU */ 323 tcp_seq t_pmtud_th_seq; /* TCP SEQ from ICMP payload */ 324 u_int t_pmtud_nextmtu; /* Advertised Next-Hop MTU from ICMP */ 325 u_short t_pmtud_ip_len; /* IP length from ICMP payload */ 326 u_short t_pmtud_ip_hl; /* IP header length from ICMP payload */ 327 328 uint8_t t_ecn_retries; /* # of ECN setup retries */ 329 330 const struct tcp_congctl *t_congctl; /* per TCB congctl algorithm */ 331 332 /* Keepalive per socket */ 333 u_int t_keepinit; 334 u_int t_keepidle; 335 u_int t_keepintvl; 336 u_int t_keepcnt; 337 u_int t_maxidle; /* t_keepcnt * t_keepintvl */ 338 339 }; 340 341 /* 342 * Macros to aid ECN TCP. 343 */ 344 #define TCP_ECN_ALLOWED(tp) (tp->t_flags & TF_ECN_PERMIT) 345 346 /* 347 * Macros to aid SACK/FACK TCP. 348 */ 349 #define TCP_SACK_ENABLED(tp) (tp->t_flags & TF_WILL_SACK) 350 #define TCP_FACK_FASTRECOV(tp) \ 351 (TCP_SACK_ENABLED(tp) && \ 352 (SEQ_GT(tp->snd_fack, tp->snd_una + tcprexmtthresh * tp->t_segsz))) 353 354 #ifdef _KERNEL 355 /* 356 * TCP reassembly queue locks. 357 */ 358 static __inline int tcp_reass_lock_try (struct tcpcb *) 359 __unused; 360 static __inline void tcp_reass_unlock (struct tcpcb *) 361 __unused; 362 363 static __inline int 364 tcp_reass_lock_try(struct tcpcb *tp) 365 { 366 int s; 367 368 /* 369 * Use splvm() -- we're blocking things that would cause 370 * mbuf allocation. 371 */ 372 s = splvm(); 373 if (tp->t_flags & TF_REASSEMBLING) { 374 splx(s); 375 return (0); 376 } 377 tp->t_flags |= TF_REASSEMBLING; 378 splx(s); 379 return (1); 380 } 381 382 static __inline void 383 tcp_reass_unlock(struct tcpcb *tp) 384 { 385 int s; 386 387 s = splvm(); 388 tp->t_flags &= ~TF_REASSEMBLING; 389 splx(s); 390 } 391 392 #ifdef DIAGNOSTIC 393 #define TCP_REASS_LOCK(tp) \ 394 do { \ 395 if (tcp_reass_lock_try(tp) == 0) { \ 396 printf("%s:%d: tcpcb %p reass already locked\n", \ 397 __FILE__, __LINE__, tp); \ 398 panic("tcp_reass_lock"); \ 399 } \ 400 } while (/*CONSTCOND*/ 0) 401 #define TCP_REASS_LOCK_CHECK(tp) \ 402 do { \ 403 if (((tp)->t_flags & TF_REASSEMBLING) == 0) { \ 404 printf("%s:%d: tcpcb %p reass lock not held\n", \ 405 __FILE__, __LINE__, tp); \ 406 panic("tcp reass lock check"); \ 407 } \ 408 } while (/*CONSTCOND*/ 0) 409 #else 410 #define TCP_REASS_LOCK(tp) (void) tcp_reass_lock_try((tp)) 411 #define TCP_REASS_LOCK_CHECK(tp) /* nothing */ 412 #endif 413 414 #define TCP_REASS_UNLOCK(tp) tcp_reass_unlock((tp)) 415 #endif /* _KERNEL */ 416 417 /* 418 * Queue for delayed ACK processing. 419 */ 420 #ifdef _KERNEL 421 extern int tcp_delack_ticks; 422 void tcp_delack(void *); 423 424 #define TCP_RESTART_DELACK(tp) \ 425 callout_reset(&(tp)->t_delack_ch, tcp_delack_ticks, \ 426 tcp_delack, tp) 427 428 #define TCP_SET_DELACK(tp) \ 429 do { \ 430 if (((tp)->t_flags & TF_DELACK) == 0) { \ 431 (tp)->t_flags |= TF_DELACK; \ 432 TCP_RESTART_DELACK(tp); \ 433 } \ 434 } while (/*CONSTCOND*/0) 435 436 #define TCP_CLEAR_DELACK(tp) \ 437 do { \ 438 if ((tp)->t_flags & TF_DELACK) { \ 439 (tp)->t_flags &= ~TF_DELACK; \ 440 callout_stop(&(tp)->t_delack_ch); \ 441 } \ 442 } while (/*CONSTCOND*/0) 443 #endif /* _KERNEL */ 444 445 /* 446 * Compute the current timestamp for a connection. 447 */ 448 #define TCP_TIMESTAMP(tp) (tcp_now - (tp)->ts_timebase) 449 450 /* 451 * Handy way of passing around TCP option info. 452 */ 453 struct tcp_opt_info { 454 int ts_present; 455 u_int32_t ts_val; 456 u_int32_t ts_ecr; 457 u_int16_t maxseg; 458 }; 459 460 #define TOF_SIGNATURE 0x0040 /* signature option present */ 461 #define TOF_SIGLEN 0x0080 /* sigature length valid (RFC2385) */ 462 463 /* 464 * Data for the TCP compressed state engine. 465 */ 466 union syn_cache_sa { 467 struct sockaddr sa; 468 struct sockaddr_in sin; 469 #if 1 /*def INET6*/ 470 struct sockaddr_in6 sin6; 471 #endif 472 }; 473 474 struct syn_cache { 475 TAILQ_ENTRY(syn_cache) sc_bucketq; /* link on bucket list */ 476 callout_t sc_timer; /* rexmt timer */ 477 struct route sc_route; 478 long sc_win; /* advertised window */ 479 int sc_bucketidx; /* our bucket index */ 480 u_int32_t sc_hash; 481 u_int32_t sc_timestamp; /* timestamp from SYN */ 482 u_int32_t sc_timebase; /* our local timebase */ 483 union syn_cache_sa sc_src; 484 union syn_cache_sa sc_dst; 485 tcp_seq sc_irs; 486 tcp_seq sc_iss; 487 u_int sc_rxtcur; /* current rxt timeout */ 488 u_int sc_rxttot; /* total time spend on queues */ 489 u_short sc_rxtshift; /* for computing backoff */ 490 u_short sc_flags; 491 492 #define SCF_UNREACH 0x0001 /* we've had an unreach error */ 493 #define SCF_TIMESTAMP 0x0002 /* peer will do timestamps */ 494 #define SCF_DEAD 0x0004 /* this entry to be released */ 495 #define SCF_SACK_PERMIT 0x0008 /* peer will do SACK */ 496 #define SCF_ECN_PERMIT 0x0010 /* peer will do ECN */ 497 #define SCF_SIGNATURE 0x40 /* send MD5 digests */ 498 499 struct mbuf *sc_ipopts; /* IP options */ 500 u_int16_t sc_peermaxseg; 501 u_int16_t sc_ourmaxseg; 502 u_int8_t sc_request_r_scale : 4, 503 sc_requested_s_scale : 4; 504 505 struct tcpcb *sc_tp; /* tcb for listening socket */ 506 LIST_ENTRY(syn_cache) sc_tpq; /* list of entries by same tp */ 507 }; 508 509 struct syn_cache_head { 510 TAILQ_HEAD(, syn_cache) sch_bucket; /* bucket entries */ 511 u_short sch_length; /* # entries in bucket */ 512 }; 513 514 #define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb) 515 #ifdef INET6 516 #define in6totcpcb(ip) ((struct tcpcb *)(ip)->in6p_ppcb) 517 #endif 518 #ifndef INET6 519 #define sototcpcb(so) (intotcpcb(sotoinpcb(so))) 520 #else 521 #define sototcpcb(so) (((so)->so_proto->pr_domain->dom_family == AF_INET) \ 522 ? intotcpcb(sotoinpcb(so)) \ 523 : in6totcpcb(sotoin6pcb(so))) 524 #endif 525 526 /* 527 * The smoothed round-trip time and estimated variance 528 * are stored as fixed point numbers scaled by the values below. 529 * For convenience, these scales are also used in smoothing the average 530 * (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed). 531 * With these scales, srtt has 3 bits to the right of the binary point, 532 * and thus an "ALPHA" of 0.875. rttvar has 2 bits to the right of the 533 * binary point, and is smoothed with an ALPHA of 0.75. 534 */ 535 #define TCP_RTT_SHIFT 3 /* shift for srtt; 3 bits frac. */ 536 #define TCP_RTTVAR_SHIFT 2 /* multiplier for rttvar; 2 bits */ 537 538 /* 539 * The initial retransmission should happen at rtt + 4 * rttvar. 540 * Because of the way we do the smoothing, srtt and rttvar 541 * will each average +1/2 tick of bias. When we compute 542 * the retransmit timer, we want 1/2 tick of rounding and 543 * 1 extra tick because of +-1/2 tick uncertainty in the 544 * firing of the timer. The bias will give us exactly the 545 * 1.5 tick we need. But, because the bias is 546 * statistical, we have to test that we don't drop below 547 * the minimum feasible timer (which is 2 ticks). 548 * This macro assumes that the value of 1<<TCP_RTTVAR_SHIFT 549 * is the same as the multiplier for rttvar. 550 */ 551 #define TCP_REXMTVAL(tp) \ 552 ((((tp)->t_srtt >> TCP_RTT_SHIFT) + (tp)->t_rttvar) >> 2) 553 554 /* 555 * Compute the initial window for slow start. 556 */ 557 #define TCP_INITIAL_WINDOW(iw, segsz) \ 558 (((iw) == 0) ? (min(4 * (segsz), max(2 * (segsz), 4380))) : \ 559 ((segsz) * (iw))) 560 561 /* 562 * TCP statistics. 563 * Each counter is an unsigned 64-bit value. 564 * 565 * Many of these should be kept per connection, but that's inconvenient 566 * at the moment. 567 */ 568 #define TCP_STAT_CONNATTEMPT 0 /* connections initiated */ 569 #define TCP_STAT_ACCEPTS 1 /* connections accepted */ 570 #define TCP_STAT_CONNECTS 2 /* connections established */ 571 #define TCP_STAT_DROPS 3 /* connections dropped */ 572 #define TCP_STAT_CONNDROPS 4 /* embryonic connections dropped */ 573 #define TCP_STAT_CLOSED 5 /* conn. closed (includes drops) */ 574 #define TCP_STAT_SEGSTIMED 6 /* segs where we tried to get rtt */ 575 #define TCP_STAT_RTTUPDATED 7 /* times we succeeded */ 576 #define TCP_STAT_DELACK 8 /* delayed ACKs sent */ 577 #define TCP_STAT_TIMEOUTDROP 9 /* conn. dropped in rxmt timeout */ 578 #define TCP_STAT_REXMTTIMEO 10 /* retransmit timeouts */ 579 #define TCP_STAT_PERSISTTIMEO 11 /* persist timeouts */ 580 #define TCP_STAT_KEEPTIMEO 12 /* keepalive timeouts */ 581 #define TCP_STAT_KEEPPROBE 13 /* keepalive probes sent */ 582 #define TCP_STAT_KEEPDROPS 14 /* connections dropped in keepalive */ 583 #define TCP_STAT_PERSISTDROPS 15 /* connections dropped in persist */ 584 #define TCP_STAT_CONNSDRAINED 16 /* connections drained due to memory 585 shortage */ 586 #define TCP_STAT_PMTUBLACKHOLE 17 /* PMTUD blackhole detected */ 587 #define TCP_STAT_SNDTOTAL 18 /* total packets sent */ 588 #define TCP_STAT_SNDPACK 19 /* data packlets sent */ 589 #define TCP_STAT_SNDBYTE 20 /* data bytes sent */ 590 #define TCP_STAT_SNDREXMITPACK 21 /* data packets retransmitted */ 591 #define TCP_STAT_SNDREXMITBYTE 22 /* data bytes retransmitted */ 592 #define TCP_STAT_SNDACKS 23 /* ACK-only packets sent */ 593 #define TCP_STAT_SNDPROBE 24 /* window probes sent */ 594 #define TCP_STAT_SNDURG 25 /* packets sent with URG only */ 595 #define TCP_STAT_SNDWINUP 26 /* window update-only packets sent */ 596 #define TCP_STAT_SNDCTRL 27 /* control (SYN|FIN|RST) packets sent */ 597 #define TCP_STAT_RCVTOTAL 28 /* total packets received */ 598 #define TCP_STAT_RCVPACK 29 /* packets received in sequence */ 599 #define TCP_STAT_RCVBYTE 30 /* bytes received in sequence */ 600 #define TCP_STAT_RCVBADSUM 31 /* packets received with cksum errs */ 601 #define TCP_STAT_RCVBADOFF 32 /* packets received with bad offset */ 602 #define TCP_STAT_RCVMEMDROP 33 /* packets dropped for lack of memory */ 603 #define TCP_STAT_RCVSHORT 34 /* packets received too short */ 604 #define TCP_STAT_RCVDUPPACK 35 /* duplicate-only packets received */ 605 #define TCP_STAT_RCVDUPBYTE 36 /* duplicate-only bytes received */ 606 #define TCP_STAT_RCVPARTDUPPACK 37 /* packets with some duplicate data */ 607 #define TCP_STAT_RCVPARTDUPBYTE 38 /* dup. bytes in part-dup. packets */ 608 #define TCP_STAT_RCVOOPACK 39 /* out-of-order packets received */ 609 #define TCP_STAT_RCVOOBYTE 40 /* out-of-order bytes received */ 610 #define TCP_STAT_RCVPACKAFTERWIN 41 /* packets with data after window */ 611 #define TCP_STAT_RCVBYTEAFTERWIN 42 /* bytes received after window */ 612 #define TCP_STAT_RCVAFTERCLOSE 43 /* packets received after "close" */ 613 #define TCP_STAT_RCVWINPROBE 44 /* rcvd window probe packets */ 614 #define TCP_STAT_RCVDUPACK 45 /* rcvd duplicate ACKs */ 615 #define TCP_STAT_RCVACKTOOMUCH 46 /* rcvd ACKs for unsent data */ 616 #define TCP_STAT_RCVACKPACK 47 /* rcvd ACK packets */ 617 #define TCP_STAT_RCVACKBYTE 48 /* bytes ACKed by rcvd ACKs */ 618 #define TCP_STAT_RCVWINUPD 49 /* rcvd window update packets */ 619 #define TCP_STAT_PAWSDROP 50 /* segments dropped due to PAWS */ 620 #define TCP_STAT_PREDACK 51 /* times hdr predict OK for ACKs */ 621 #define TCP_STAT_PREDDAT 52 /* times hdr predict OK for data pkts */ 622 #define TCP_STAT_PCBHASHMISS 53 /* input packets missing PCB hash */ 623 #define TCP_STAT_NOPORT 54 /* no socket on port */ 624 #define TCP_STAT_BADSYN 55 /* received ACK for which we have 625 no SYN in compressed state */ 626 #define TCP_STAT_DELAYED_FREE 56 /* delayed pool_put() of tcpcb */ 627 #define TCP_STAT_SC_ADDED 57 /* # of sc entries added */ 628 #define TCP_STAT_SC_COMPLETED 58 /* # of sc connections completed */ 629 #define TCP_STAT_SC_TIMED_OUT 59 /* # of sc entries timed out */ 630 #define TCP_STAT_SC_OVERFLOWED 60 /* # of sc drops due to overflow */ 631 #define TCP_STAT_SC_RESET 61 /* # of sc drops due to RST */ 632 #define TCP_STAT_SC_UNREACH 62 /* # of sc drops due to ICMP unreach */ 633 #define TCP_STAT_SC_BUCKETOVERFLOW 63 /* # of sc drops due to bucket ovflow */ 634 #define TCP_STAT_SC_ABORTED 64 /* # of sc entries aborted (no mem) */ 635 #define TCP_STAT_SC_DUPESYN 65 /* # of duplicate SYNs received */ 636 #define TCP_STAT_SC_DROPPED 66 /* # of SYNs dropped (no route/mem) */ 637 #define TCP_STAT_SC_COLLISIONS 67 /* # of sc hash collisions */ 638 #define TCP_STAT_SC_RETRANSMITTED 68 /* # of sc retransmissions */ 639 #define TCP_STAT_SC_DELAYED_FREE 69 /* # of delayed pool_put()s */ 640 #define TCP_STAT_SELFQUENCH 70 /* # of ENOBUFS we get on output */ 641 #define TCP_STAT_BADSIG 71 /* # of drops due to bad signature */ 642 #define TCP_STAT_GOODSIG 72 /* # of packets with good signature */ 643 #define TCP_STAT_ECN_SHS 73 /* # of successful ECN handshakes */ 644 #define TCP_STAT_ECN_CE 74 /* # of packets with CE bit */ 645 #define TCP_STAT_ECN_ECT 75 /* # of packets with ECT(0) bit */ 646 647 #define TCP_NSTATS 76 648 649 /* 650 * Names for TCP sysctl objects. 651 */ 652 #define TCPCTL_RFC1323 1 /* RFC1323 timestamps/scaling */ 653 #define TCPCTL_SENDSPACE 2 /* default send buffer */ 654 #define TCPCTL_RECVSPACE 3 /* default recv buffer */ 655 #define TCPCTL_MSSDFLT 4 /* default seg size */ 656 #define TCPCTL_SYN_CACHE_LIMIT 5 /* max size of comp. state engine */ 657 #define TCPCTL_SYN_BUCKET_LIMIT 6 /* max size of hash bucket */ 658 #if 0 /*obsoleted*/ 659 #define TCPCTL_SYN_CACHE_INTER 7 /* interval of comp. state timer */ 660 #endif 661 #define TCPCTL_INIT_WIN 8 /* initial window */ 662 #define TCPCTL_MSS_IFMTU 9 /* mss from interface, not in_maxmtu */ 663 #define TCPCTL_SACK 10 /* RFC2018 selective acknowledgement */ 664 #define TCPCTL_WSCALE 11 /* RFC1323 window scaling */ 665 #define TCPCTL_TSTAMP 12 /* RFC1323 timestamps */ 666 #define TCPCTL_COMPAT_42 13 /* 4.2BSD TCP bug work-arounds */ 667 #define TCPCTL_CWM 14 /* Congestion Window Monitoring */ 668 #define TCPCTL_CWM_BURSTSIZE 15 /* burst size allowed by CWM */ 669 #define TCPCTL_ACK_ON_PUSH 16 /* ACK immediately on PUSH */ 670 #define TCPCTL_KEEPIDLE 17 /* keepalive idle time */ 671 #define TCPCTL_KEEPINTVL 18 /* keepalive probe interval */ 672 #define TCPCTL_KEEPCNT 19 /* keepalive count */ 673 #define TCPCTL_SLOWHZ 20 /* PR_SLOWHZ (read-only) */ 674 #define TCPCTL_NEWRENO 21 /* NewReno Congestion Control */ 675 #define TCPCTL_LOG_REFUSED 22 /* Log refused connections */ 676 #if 0 /*obsoleted*/ 677 #define TCPCTL_RSTRATELIMIT 23 /* RST rate limit */ 678 #endif 679 #define TCPCTL_RSTPPSLIMIT 24 /* RST pps limit */ 680 #define TCPCTL_DELACK_TICKS 25 /* # ticks to delay ACK */ 681 #define TCPCTL_INIT_WIN_LOCAL 26 /* initial window for local nets */ 682 #define TCPCTL_IDENT 27 /* rfc 931 identd */ 683 #define TCPCTL_ACKDROPRATELIMIT 28 /* SYN/RST -> ACK rate limit */ 684 #define TCPCTL_LOOPBACKCKSUM 29 /* do TCP checksum on loopback */ 685 #define TCPCTL_STATS 30 /* TCP statistics */ 686 #define TCPCTL_DEBUG 31 /* TCP debug sockets */ 687 #define TCPCTL_DEBX 32 /* # of tcp debug sockets */ 688 #define TCPCTL_DROP 33 /* drop tcp connection */ 689 #define TCPCTL_MAXID 34 690 691 #define TCPCTL_NAMES { \ 692 { 0, 0 }, \ 693 { "rfc1323", CTLTYPE_INT }, \ 694 { "sendspace", CTLTYPE_INT }, \ 695 { "recvspace", CTLTYPE_INT }, \ 696 { "mssdflt", CTLTYPE_INT }, \ 697 { "syn_cache_limit", CTLTYPE_INT }, \ 698 { "syn_bucket_limit", CTLTYPE_INT }, \ 699 { 0, 0 },\ 700 { "init_win", CTLTYPE_INT }, \ 701 { "mss_ifmtu", CTLTYPE_INT }, \ 702 { "sack", CTLTYPE_INT }, \ 703 { "win_scale", CTLTYPE_INT }, \ 704 { "timestamps", CTLTYPE_INT }, \ 705 { "compat_42", CTLTYPE_INT }, \ 706 { "cwm", CTLTYPE_INT }, \ 707 { "cwm_burstsize", CTLTYPE_INT }, \ 708 { "ack_on_push", CTLTYPE_INT }, \ 709 { "keepidle", CTLTYPE_INT }, \ 710 { "keepintvl", CTLTYPE_INT }, \ 711 { "keepcnt", CTLTYPE_INT }, \ 712 { "slowhz", CTLTYPE_INT }, \ 713 { 0, 0 }, \ 714 { "log_refused",CTLTYPE_INT }, \ 715 { 0, 0 }, \ 716 { "rstppslimit", CTLTYPE_INT }, \ 717 { "delack_ticks", CTLTYPE_INT }, \ 718 { "init_win_local", CTLTYPE_INT }, \ 719 { "ident", CTLTYPE_STRUCT }, \ 720 { "ackdropppslimit", CTLTYPE_INT }, \ 721 { "do_loopback_cksum", CTLTYPE_INT }, \ 722 { "stats", CTLTYPE_STRUCT }, \ 723 { "debug", CTLTYPE_STRUCT }, \ 724 { "debx", CTLTYPE_INT }, \ 725 { "drop", CTLTYPE_STRUCT }, \ 726 } 727 728 #ifdef _KERNEL 729 extern struct inpcbtable tcbtable; /* head of queue of active tcpcb's */ 730 extern u_int32_t tcp_now; /* for RFC 1323 timestamps */ 731 extern int tcp_do_rfc1323; /* enabled/disabled? */ 732 extern int tcp_do_sack; /* SACK enabled/disabled? */ 733 extern int tcp_do_win_scale; /* RFC1323 window scaling enabled/disabled? */ 734 extern int tcp_do_timestamps; /* RFC1323 timestamps enabled/disabled? */ 735 extern int tcp_mssdflt; /* default seg size */ 736 extern int tcp_minmss; /* minimal seg size */ 737 extern int tcp_init_win; /* initial window */ 738 extern int tcp_init_win_local; /* initial window for local nets */ 739 extern int tcp_mss_ifmtu; /* take MSS from interface, not in_maxmtu */ 740 extern int tcp_compat_42; /* work around ancient broken TCP peers */ 741 extern int tcp_cwm; /* enable Congestion Window Monitoring */ 742 extern int tcp_cwm_burstsize; /* burst size allowed by CWM */ 743 extern int tcp_ack_on_push; /* ACK immediately on PUSH */ 744 extern int tcp_syn_cache_limit; /* max entries for compressed state engine */ 745 extern int tcp_syn_bucket_limit;/* max entries per hash bucket */ 746 extern int tcp_log_refused; /* log refused connections */ 747 extern int tcp_do_ecn; /* TCP ECN enabled/disabled? */ 748 extern int tcp_ecn_maxretries; /* Max ECN setup retries */ 749 #if NRND > 0 750 extern int tcp_do_rfc1948; /* ISS by cryptographic hash */ 751 #endif 752 extern int tcp_sack_tp_maxholes; /* Max holes per connection. */ 753 extern int tcp_sack_globalmaxholes; /* Max holes per system. */ 754 extern int tcp_sack_globalholes; /* Number of holes present. */ 755 extern int tcp_do_abc; /* RFC3465 ABC enabled/disabled? */ 756 extern int tcp_abc_aggressive; /* 1: L=2*SMSS 0: L=1*SMSS */ 757 758 extern int tcp_rst_ppslim; 759 extern int tcp_ackdrop_ppslim; 760 761 extern int tcp_syn_cache_size; 762 extern struct syn_cache_head tcp_syn_cache[]; 763 extern u_long syn_cache_count; 764 765 #ifdef MBUFTRACE 766 extern struct mowner tcp_rx_mowner; 767 extern struct mowner tcp_tx_mowner; 768 extern struct mowner tcp_reass_mowner; 769 extern struct mowner tcp_sock_mowner; 770 extern struct mowner tcp_sock_rx_mowner; 771 extern struct mowner tcp_sock_tx_mowner; 772 extern struct mowner tcp_mowner; 773 #endif 774 775 extern int tcp_do_autorcvbuf; 776 extern int tcp_autorcvbuf_inc; 777 extern int tcp_autorcvbuf_max; 778 extern int tcp_do_autosndbuf; 779 extern int tcp_autosndbuf_inc; 780 extern int tcp_autosndbuf_max; 781 782 783 #define TCPCTL_VARIABLES { \ 784 { 0 }, \ 785 { 1, 0, &tcp_do_rfc1323 }, \ 786 { 1, 0, &tcp_sendspace }, \ 787 { 1, 0, &tcp_recvspace }, \ 788 { 1, 0, &tcp_mssdflt }, \ 789 { 1, 0, &tcp_syn_cache_limit }, \ 790 { 1, 0, &tcp_syn_bucket_limit }, \ 791 { 0 }, \ 792 { 1, 0, &tcp_init_win }, \ 793 { 1, 0, &tcp_mss_ifmtu }, \ 794 { 1, 0, &tcp_do_sack }, \ 795 { 1, 0, &tcp_do_win_scale }, \ 796 { 1, 0, &tcp_do_timestamps }, \ 797 { 1, 0, &tcp_compat_42 }, \ 798 { 1, 0, &tcp_cwm }, \ 799 { 1, 0, &tcp_cwm_burstsize }, \ 800 { 1, 0, &tcp_ack_on_push }, \ 801 { 1, 0, &tcp_keepidle }, \ 802 { 1, 0, &tcp_keepintvl }, \ 803 { 1, 0, &tcp_keepcnt }, \ 804 { 1, 1, 0, PR_SLOWHZ }, \ 805 { 0 }, \ 806 { 1, 0, &tcp_log_refused }, \ 807 { 0 }, \ 808 { 1, 0, &tcp_rst_ppslim }, \ 809 { 1, 0, &tcp_delack_ticks }, \ 810 { 1, 0, &tcp_init_win_local }, \ 811 { 1, 0, &tcp_ackdrop_ppslim }, \ 812 } 813 814 struct secasvar; 815 816 int tcp_attach(struct socket *); 817 void tcp_canceltimers(struct tcpcb *); 818 struct tcpcb * 819 tcp_close(struct tcpcb *); 820 int tcp_isdead(struct tcpcb *); 821 #ifdef INET6 822 void *tcp6_ctlinput(int, const struct sockaddr *, void *); 823 #endif 824 void *tcp_ctlinput(int, const struct sockaddr *, void *); 825 int tcp_ctloutput(int, struct socket *, struct sockopt *); 826 struct tcpcb * 827 tcp_disconnect(struct tcpcb *); 828 struct tcpcb * 829 tcp_drop(struct tcpcb *, int); 830 #ifdef TCP_SIGNATURE 831 int tcp_signature_apply(void *, void *, u_int); 832 struct secasvar *tcp_signature_getsav(struct mbuf *, struct tcphdr *); 833 int tcp_signature(struct mbuf *, struct tcphdr *, int, struct secasvar *, 834 char *); 835 #endif 836 void tcp_drain(void); 837 void tcp_established(struct tcpcb *); 838 void tcp_init(void); 839 #ifdef INET6 840 int tcp6_input(struct mbuf **, int *, int); 841 #endif 842 void tcp_input(struct mbuf *, ...); 843 u_int tcp_hdrsz(struct tcpcb *); 844 u_long tcp_mss_to_advertise(const struct ifnet *, int); 845 void tcp_mss_from_peer(struct tcpcb *, int); 846 void tcp_tcpcb_template(void); 847 struct tcpcb * 848 tcp_newtcpcb(int, void *); 849 void tcp_notify(struct inpcb *, int); 850 #ifdef INET6 851 void tcp6_notify(struct in6pcb *, int); 852 #endif 853 u_int tcp_optlen(struct tcpcb *); 854 int tcp_output(struct tcpcb *); 855 void tcp_pulloutofband(struct socket *, 856 struct tcphdr *, struct mbuf *, int); 857 void tcp_quench(struct inpcb *, int); 858 #ifdef INET6 859 void tcp6_quench(struct in6pcb *, int); 860 #endif 861 void tcp_mtudisc(struct inpcb *, int); 862 863 struct ipqent *tcpipqent_alloc(void); 864 void tcpipqent_free(struct ipqent *); 865 866 int tcp_respond(struct tcpcb *, struct mbuf *, struct mbuf *, 867 struct tcphdr *, tcp_seq, tcp_seq, int); 868 void tcp_rmx_rtt(struct tcpcb *); 869 void tcp_setpersist(struct tcpcb *); 870 #ifdef TCP_SIGNATURE 871 int tcp_signature_compute(struct mbuf *, struct tcphdr *, int, int, 872 int, u_char *, u_int); 873 #endif 874 void tcp_slowtimo(void); 875 struct mbuf * 876 tcp_template(struct tcpcb *); 877 void tcp_trace(short, short, struct tcpcb *, struct mbuf *, int); 878 struct tcpcb * 879 tcp_usrclosed(struct tcpcb *); 880 int tcp_usrreq(struct socket *, 881 int, struct mbuf *, struct mbuf *, struct mbuf *, struct lwp *); 882 void tcp_xmit_timer(struct tcpcb *, uint32_t); 883 tcp_seq tcp_new_iss(struct tcpcb *, tcp_seq); 884 tcp_seq tcp_new_iss1(void *, void *, u_int16_t, u_int16_t, size_t, 885 tcp_seq); 886 887 void tcp_new_dsack(struct tcpcb *, tcp_seq, u_int32_t); 888 void tcp_sack_option(struct tcpcb *, const struct tcphdr *, 889 const u_char *, int); 890 void tcp_del_sackholes(struct tcpcb *, const struct tcphdr *); 891 void tcp_free_sackholes(struct tcpcb *); 892 void tcp_sack_adjust(struct tcpcb *tp); 893 struct sackhole *tcp_sack_output(struct tcpcb *tp, int *sack_bytes_rexmt); 894 void tcp_sack_newack(struct tcpcb *, const struct tcphdr *); 895 int tcp_sack_numblks(const struct tcpcb *); 896 #define TCP_SACK_OPTLEN(nblks) ((nblks) * 8 + 2 + 2) 897 898 void tcp_statinc(u_int); 899 void tcp_statadd(u_int, uint64_t); 900 901 int syn_cache_add(struct sockaddr *, struct sockaddr *, 902 struct tcphdr *, unsigned int, struct socket *, 903 struct mbuf *, u_char *, int, struct tcp_opt_info *); 904 void syn_cache_unreach(const struct sockaddr *, const struct sockaddr *, 905 struct tcphdr *); 906 struct socket *syn_cache_get(struct sockaddr *, struct sockaddr *, 907 struct tcphdr *, unsigned int, unsigned int, 908 struct socket *so, struct mbuf *); 909 void syn_cache_init(void); 910 void syn_cache_insert(struct syn_cache *, struct tcpcb *); 911 struct syn_cache *syn_cache_lookup(const struct sockaddr *, const struct sockaddr *, 912 struct syn_cache_head **); 913 void syn_cache_reset(struct sockaddr *, struct sockaddr *, 914 struct tcphdr *); 915 int syn_cache_respond(struct syn_cache *, struct mbuf *); 916 void syn_cache_timer(void *); 917 void syn_cache_cleanup(struct tcpcb *); 918 919 int tcp_input_checksum(int, struct mbuf *, const struct tcphdr *, int, int, 920 int); 921 #endif 922 923 #endif /* !_NETINET_TCP_VAR_H_ */ 924
Indexes created Mon Sep 22 13:09:51 GMT 2025