tcp_var.h revision 1.116
1 /* $NetBSD: tcp_var.h,v 1.116 2005/01/26 21:49:27 mycroft 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 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 * 80 * Redistribution and use in source and binary forms, with or without 81 * modification, are permitted provided that the following conditions 82 * are met: 83 * 1. Redistributions of source code must retain the above copyright 84 * notice, this list of conditions and the following disclaimer. 85 * 2. Redistributions in binary form must reproduce the above copyright 86 * notice, this list of conditions and the following disclaimer in the 87 * documentation and/or other materials provided with the distribution. 88 * 3. All advertising materials mentioning features or use of this software 89 * must display the following acknowledgement: 90 * This product includes software developed by the NetBSD 91 * Foundation, Inc. and its contributors. 92 * 4. Neither the name of The NetBSD Foundation nor the names of its 93 * contributors may be used to endorse or promote products derived 94 * from this software without specific prior written permission. 95 * 96 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 97 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 98 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 99 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 100 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 101 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 102 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 103 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 104 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 105 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 106 * POSSIBILITY OF SUCH DAMAGE. 107 */ 108 109 /* 110 * Copyright (c) 1982, 1986, 1993, 1994, 1995 111 * The Regents of the University of California. All rights reserved. 112 * 113 * Redistribution and use in source and binary forms, with or without 114 * modification, are permitted provided that the following conditions 115 * are met: 116 * 1. Redistributions of source code must retain the above copyright 117 * notice, this list of conditions and the following disclaimer. 118 * 2. Redistributions in binary form must reproduce the above copyright 119 * notice, this list of conditions and the following disclaimer in the 120 * documentation and/or other materials provided with the distribution. 121 * 3. Neither the name of the University nor the names of its contributors 122 * may be used to endorse or promote products derived from this software 123 * without specific prior written permission. 124 * 125 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 126 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 127 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 128 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 129 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 130 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 131 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 132 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 133 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 134 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 135 * SUCH DAMAGE. 136 * 137 * @(#)tcp_var.h 8.4 (Berkeley) 5/24/95 138 */ 139 140 #ifndef _NETINET_TCP_VAR_H_ 141 #define _NETINET_TCP_VAR_H_ 142 143 #if defined(_KERNEL_OPT) 144 #include "opt_inet.h" 145 #include "opt_mbuftrace.h" 146 #endif 147 148 /* 149 * Kernel variables for tcp. 150 */ 151 152 #include <sys/callout.h> 153 154 #ifdef TCP_SIGNATURE 155 /* 156 * Defines which are needed by the xform_tcp module and tcp_[in|out]put 157 * for SADB verification and lookup. 158 */ 159 #define TCP_SIGLEN 16 /* length of computed digest in bytes */ 160 #define TCP_KEYLEN_MIN 1 /* minimum length of TCP-MD5 key */ 161 #define TCP_KEYLEN_MAX 80 /* maximum length of TCP-MD5 key */ 162 /* 163 * Only a single SA per host may be specified at this time. An SPI is 164 * needed in order for the KEY_ALLOCSA() lookup to work. 165 */ 166 #define TCP_SIG_SPI 0x1000 167 #endif /* TCP_SIGNATURE */ 168 169 /* 170 * Tcp control block, one per tcp; fields: 171 */ 172 struct tcpcb { 173 int t_family; /* address family on the wire */ 174 struct ipqehead segq; /* sequencing queue */ 175 struct callout t_timer[TCPT_NTIMERS];/* tcp timers */ 176 short t_state; /* state of this connection */ 177 short t_rxtshift; /* log(2) of rexmt exp. backoff */ 178 uint32_t t_rxtcur; /* current retransmit value */ 179 short t_dupacks; /* consecutive dup acks recd */ 180 u_short t_peermss; /* peer's maximum segment size */ 181 u_short t_ourmss; /* our's maximum segment size */ 182 u_short t_segsz; /* current segment size in use */ 183 char t_force; /* 1 if forcing out a byte */ 184 u_int t_flags; 185 #define TF_ACKNOW 0x0001 /* ack peer immediately */ 186 #define TF_DELACK 0x0002 /* ack, but try to delay it */ 187 #define TF_NODELAY 0x0004 /* don't delay packets to coalesce */ 188 #define TF_NOOPT 0x0008 /* don't use tcp options */ 189 #define TF_REQ_SCALE 0x0020 /* have/will request window scaling */ 190 #define TF_RCVD_SCALE 0x0040 /* other side has requested scaling */ 191 #define TF_REQ_TSTMP 0x0080 /* have/will request timestamps */ 192 #define TF_RCVD_TSTMP 0x0100 /* a timestamp was received in SYN */ 193 #define TF_SACK_PERMIT 0x0200 /* other side said I could SACK */ 194 #define TF_SYN_REXMT 0x0400 /* rexmit timer fired on SYN */ 195 #define TF_WILL_SACK 0x0800 /* try to use SACK */ 196 #define TF_CANT_TXSACK 0x1000 /* other side said I could not SACK */ 197 #define TF_IGNR_RXSACK 0x2000 /* ignore received SACK blocks */ 198 #define TF_REASSEMBLING 0x4000 /* we're busy reassembling */ 199 #define TF_DEAD 0x8000 /* dead and to-be-released */ 200 #define TF_SIGNATURE 0x400000 /* require MD5 digests (RFC2385) */ 201 202 203 struct mbuf *t_template; /* skeletal packet for transmit */ 204 struct inpcb *t_inpcb; /* back pointer to internet pcb */ 205 struct in6pcb *t_in6pcb; /* back pointer to internet pcb */ 206 struct callout t_delack_ch; /* delayed ACK callout */ 207 /* 208 * The following fields are used as in the protocol specification. 209 * See RFC783, Dec. 1981, page 21. 210 */ 211 /* send sequence variables */ 212 tcp_seq snd_una; /* send unacknowledged */ 213 tcp_seq snd_nxt; /* send next */ 214 tcp_seq snd_up; /* send urgent pointer */ 215 tcp_seq snd_wl1; /* window update seg seq number */ 216 tcp_seq snd_wl2; /* window update seg ack number */ 217 tcp_seq iss; /* initial send sequence number */ 218 u_long snd_wnd; /* send window */ 219 tcp_seq snd_recover; /* for use in fast recovery */ 220 tcp_seq snd_high; /* NewReno false fast rexmit counter */ 221 /* receive sequence variables */ 222 u_long rcv_wnd; /* receive window */ 223 tcp_seq rcv_nxt; /* receive next */ 224 tcp_seq rcv_up; /* receive urgent pointer */ 225 tcp_seq irs; /* initial receive sequence number */ 226 /* 227 * Additional variables for this implementation. 228 */ 229 /* receive variables */ 230 tcp_seq rcv_adv; /* advertised window */ 231 /* retransmit variables */ 232 tcp_seq snd_max; /* highest sequence number sent; 233 * used to recognize retransmits 234 */ 235 /* congestion control (for slow start, source quench, retransmit after loss) */ 236 u_long snd_cwnd; /* congestion-controlled window */ 237 u_long snd_ssthresh; /* snd_cwnd size threshhold for 238 * for slow start exponential to 239 * linear switch 240 */ 241 /* 242 * transmit timing stuff. See below for scale of srtt and rttvar. 243 * "Variance" is actually smoothed difference. 244 */ 245 uint32_t t_rcvtime; /* time last segment received */ 246 uint32_t t_rtttime; /* time we started measuring rtt */ 247 tcp_seq t_rtseq; /* sequence number being timed */ 248 int32_t t_srtt; /* smoothed round-trip time */ 249 int32_t t_rttvar; /* variance in round-trip time */ 250 uint32_t t_rttmin; /* minimum rtt allowed */ 251 u_long max_sndwnd; /* largest window peer has offered */ 252 253 /* out-of-band data */ 254 char t_oobflags; /* have some */ 255 char t_iobc; /* input character */ 256 #define TCPOOB_HAVEDATA 0x01 257 #define TCPOOB_HADDATA 0x02 258 short t_softerror; /* possible error not yet reported */ 259 260 /* RFC 1323 variables */ 261 u_char snd_scale; /* window scaling for send window */ 262 u_char rcv_scale; /* window scaling for recv window */ 263 u_char request_r_scale; /* pending window scaling */ 264 u_char requested_s_scale; 265 u_int32_t ts_recent; /* timestamp echo data */ 266 u_int32_t ts_recent_age; /* when last updated */ 267 u_int32_t ts_timebase; /* our timebase */ 268 tcp_seq last_ack_sent; 269 270 /* SACK stuff */ 271 struct ipqehead timeq; /* time sequenced queue (for SACK) */ 272 273 /* path MTU discovery blackhole detection */ 274 int t_mtudisc; /* perform mtudisc for this tcb */ 275 276 /* pointer for syn cache entries*/ 277 LIST_HEAD(, syn_cache) t_sc; /* list of entries by this tcb */ 278 279 /* prediction of next mbuf when using large window sizes */ 280 struct mbuf *t_lastm; /* last mbuf that data was sent from */ 281 int t_inoff; /* data offset in previous mbuf */ 282 int t_lastoff; /* last data address in mbuf chain */ 283 int t_lastlen; /* last length read from mbuf chain */ 284 }; 285 286 #ifdef _KERNEL 287 /* 288 * TCP reassembly queue locks. 289 */ 290 static __inline int tcp_reass_lock_try (struct tcpcb *) 291 __attribute__((__unused__)); 292 static __inline void tcp_reass_unlock (struct tcpcb *) 293 __attribute__((__unused__)); 294 295 static __inline int 296 tcp_reass_lock_try(tp) 297 struct tcpcb *tp; 298 { 299 int s; 300 301 /* 302 * Use splvm() -- we're blocking things that would cause 303 * mbuf allocation. 304 */ 305 s = splvm(); 306 if (tp->t_flags & TF_REASSEMBLING) { 307 splx(s); 308 return (0); 309 } 310 tp->t_flags |= TF_REASSEMBLING; 311 splx(s); 312 return (1); 313 } 314 315 static __inline void 316 tcp_reass_unlock(tp) 317 struct tcpcb *tp; 318 { 319 int s; 320 321 s = splvm(); 322 tp->t_flags &= ~TF_REASSEMBLING; 323 splx(s); 324 } 325 326 #ifdef DIAGNOSTIC 327 #define TCP_REASS_LOCK(tp) \ 328 do { \ 329 if (tcp_reass_lock_try(tp) == 0) { \ 330 printf("%s:%d: tcpcb %p reass already locked\n", \ 331 __FILE__, __LINE__, tp); \ 332 panic("tcp_reass_lock"); \ 333 } \ 334 } while (/*CONSTCOND*/ 0) 335 #define TCP_REASS_LOCK_CHECK(tp) \ 336 do { \ 337 if (((tp)->t_flags & TF_REASSEMBLING) == 0) { \ 338 printf("%s:%d: tcpcb %p reass lock not held\n", \ 339 __FILE__, __LINE__, tp); \ 340 panic("tcp reass lock check"); \ 341 } \ 342 } while (/*CONSTCOND*/ 0) 343 #else 344 #define TCP_REASS_LOCK(tp) (void) tcp_reass_lock_try((tp)) 345 #define TCP_REASS_LOCK_CHECK(tp) /* nothing */ 346 #endif 347 348 #define TCP_REASS_UNLOCK(tp) tcp_reass_unlock((tp)) 349 #endif /* _KERNEL */ 350 351 /* 352 * Queue for delayed ACK processing. 353 */ 354 #ifdef _KERNEL 355 extern int tcp_delack_ticks; 356 void tcp_delack(void *); 357 358 #define TCP_RESTART_DELACK(tp) \ 359 callout_reset(&(tp)->t_delack_ch, tcp_delack_ticks, \ 360 tcp_delack, tp) 361 362 #define TCP_SET_DELACK(tp) \ 363 do { \ 364 if (((tp)->t_flags & TF_DELACK) == 0) { \ 365 (tp)->t_flags |= TF_DELACK; \ 366 TCP_RESTART_DELACK(tp); \ 367 } \ 368 } while (/*CONSTCOND*/0) 369 370 #define TCP_CLEAR_DELACK(tp) \ 371 do { \ 372 if ((tp)->t_flags & TF_DELACK) { \ 373 (tp)->t_flags &= ~TF_DELACK; \ 374 callout_stop(&(tp)->t_delack_ch); \ 375 } \ 376 } while (/*CONSTCOND*/0) 377 #endif /* _KERNEL */ 378 379 /* 380 * Compute the current timestamp for a connection. 381 */ 382 #define TCP_TIMESTAMP(tp) (tcp_now - (tp)->ts_timebase) 383 384 /* 385 * Handy way of passing around TCP option info. 386 */ 387 struct tcp_opt_info { 388 int ts_present; 389 u_int32_t ts_val; 390 u_int32_t ts_ecr; 391 u_int16_t maxseg; 392 }; 393 394 #define TOF_SIGNATURE 0x0040 /* signature option present */ 395 #define TOF_SIGLEN 0x0080 /* sigature length valid (RFC2385) */ 396 397 /* 398 * Data for the TCP compressed state engine. 399 */ 400 union syn_cache_sa { 401 struct sockaddr sa; 402 struct sockaddr_in sin; 403 #if 1 /*def INET6*/ 404 struct sockaddr_in6 sin6; 405 #endif 406 }; 407 408 struct syn_cache { 409 TAILQ_ENTRY(syn_cache) sc_bucketq; /* link on bucket list */ 410 struct callout sc_timer; /* rexmt timer */ 411 union { /* cached route */ 412 struct route route4; 413 #ifdef INET6 414 struct route_in6 route6; 415 #endif 416 } sc_route_u; 417 #define sc_route4 sc_route_u.route4 418 #ifdef INET6 419 #define sc_route6 sc_route_u.route6 420 #endif 421 long sc_win; /* advertised window */ 422 int sc_bucketidx; /* our bucket index */ 423 u_int32_t sc_hash; 424 u_int32_t sc_timestamp; /* timestamp from SYN */ 425 u_int32_t sc_timebase; /* our local timebase */ 426 union syn_cache_sa sc_src; 427 union syn_cache_sa sc_dst; 428 tcp_seq sc_irs; 429 tcp_seq sc_iss; 430 u_int sc_rxtcur; /* current rxt timeout */ 431 u_int sc_rxttot; /* total time spend on queues */ 432 u_short sc_rxtshift; /* for computing backoff */ 433 u_short sc_flags; 434 435 #define SCF_UNREACH 0x0001 /* we've had an unreach error */ 436 #define SCF_TIMESTAMP 0x0002 /* peer will do timestamps */ 437 #define SCF_DEAD 0x0004 /* this entry to be released */ 438 #define SCF_SIGNATURE 0x40 /* send MD5 digests */ 439 440 struct mbuf *sc_ipopts; /* IP options */ 441 u_int16_t sc_peermaxseg; 442 u_int16_t sc_ourmaxseg; 443 u_int8_t sc_request_r_scale : 4, 444 sc_requested_s_scale : 4; 445 446 struct tcpcb *sc_tp; /* tcb for listening socket */ 447 LIST_ENTRY(syn_cache) sc_tpq; /* list of entries by same tp */ 448 }; 449 450 struct syn_cache_head { 451 TAILQ_HEAD(, syn_cache) sch_bucket; /* bucket entries */ 452 u_short sch_length; /* # entries in bucket */ 453 }; 454 455 #define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb) 456 #ifdef INET6 457 #define in6totcpcb(ip) ((struct tcpcb *)(ip)->in6p_ppcb) 458 #endif 459 #ifndef INET6 460 #define sototcpcb(so) (intotcpcb(sotoinpcb(so))) 461 #else 462 #define sototcpcb(so) (((so)->so_proto->pr_domain->dom_family == AF_INET) \ 463 ? intotcpcb(sotoinpcb(so)) \ 464 : in6totcpcb(sotoin6pcb(so))) 465 #endif 466 467 /* 468 * The smoothed round-trip time and estimated variance 469 * are stored as fixed point numbers scaled by the values below. 470 * For convenience, these scales are also used in smoothing the average 471 * (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed). 472 * With these scales, srtt has 3 bits to the right of the binary point, 473 * and thus an "ALPHA" of 0.875. rttvar has 2 bits to the right of the 474 * binary point, and is smoothed with an ALPHA of 0.75. 475 */ 476 #define TCP_RTT_SHIFT 3 /* shift for srtt; 3 bits frac. */ 477 #define TCP_RTTVAR_SHIFT 2 /* multiplier for rttvar; 2 bits */ 478 479 /* 480 * The initial retransmission should happen at rtt + 4 * rttvar. 481 * Because of the way we do the smoothing, srtt and rttvar 482 * will each average +1/2 tick of bias. When we compute 483 * the retransmit timer, we want 1/2 tick of rounding and 484 * 1 extra tick because of +-1/2 tick uncertainty in the 485 * firing of the timer. The bias will give us exactly the 486 * 1.5 tick we need. But, because the bias is 487 * statistical, we have to test that we don't drop below 488 * the minimum feasible timer (which is 2 ticks). 489 * This macro assumes that the value of 1<<TCP_RTTVAR_SHIFT 490 * is the same as the multiplier for rttvar. 491 */ 492 #define TCP_REXMTVAL(tp) \ 493 ((((tp)->t_srtt >> TCP_RTT_SHIFT) + (tp)->t_rttvar) >> 2) 494 495 /* 496 * Compute the initial window for slow start. 497 */ 498 #define TCP_INITIAL_WINDOW(iw, segsz) \ 499 (((iw) == 0) ? (min(4 * (segsz), max(2 * (segsz), 4380))) : \ 500 ((segsz) * (iw))) 501 502 /* 503 * TCP statistics. 504 * Many of these should be kept per connection, 505 * but that's inconvenient at the moment. 506 */ 507 struct tcpstat { 508 u_quad_t tcps_connattempt; /* connections initiated */ 509 u_quad_t tcps_accepts; /* connections accepted */ 510 u_quad_t tcps_connects; /* connections established */ 511 u_quad_t tcps_drops; /* connections dropped */ 512 u_quad_t tcps_conndrops; /* embryonic connections dropped */ 513 u_quad_t tcps_closed; /* conn. closed (includes drops) */ 514 u_quad_t tcps_segstimed; /* segs where we tried to get rtt */ 515 u_quad_t tcps_rttupdated; /* times we succeeded */ 516 u_quad_t tcps_delack; /* delayed acks sent */ 517 u_quad_t tcps_timeoutdrop; /* conn. dropped in rxmt timeout */ 518 u_quad_t tcps_rexmttimeo; /* retransmit timeouts */ 519 u_quad_t tcps_persisttimeo; /* persist timeouts */ 520 u_quad_t tcps_keeptimeo; /* keepalive timeouts */ 521 u_quad_t tcps_keepprobe; /* keepalive probes sent */ 522 u_quad_t tcps_keepdrops; /* connections dropped in keepalive */ 523 u_quad_t tcps_persistdrops; /* connections dropped in persist */ 524 u_quad_t tcps_connsdrained; /* connections drained due to memory 525 shortage */ 526 u_quad_t tcps_pmtublackhole; /* PMTUD blackhole detected */ 527 528 u_quad_t tcps_sndtotal; /* total packets sent */ 529 u_quad_t tcps_sndpack; /* data packets sent */ 530 u_quad_t tcps_sndbyte; /* data bytes sent */ 531 u_quad_t tcps_sndrexmitpack; /* data packets retransmitted */ 532 u_quad_t tcps_sndrexmitbyte; /* data bytes retransmitted */ 533 u_quad_t tcps_sndacks; /* ack-only packets sent */ 534 u_quad_t tcps_sndprobe; /* window probes sent */ 535 u_quad_t tcps_sndurg; /* packets sent with URG only */ 536 u_quad_t tcps_sndwinup; /* window update-only packets sent */ 537 u_quad_t tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */ 538 539 u_quad_t tcps_rcvtotal; /* total packets received */ 540 u_quad_t tcps_rcvpack; /* packets received in sequence */ 541 u_quad_t tcps_rcvbyte; /* bytes received in sequence */ 542 u_quad_t tcps_rcvbadsum; /* packets received with ccksum errs */ 543 u_quad_t tcps_rcvbadoff; /* packets received with bad offset */ 544 u_quad_t tcps_rcvmemdrop; /* packets dropped for lack of memory */ 545 u_quad_t tcps_rcvshort; /* packets received too short */ 546 u_quad_t tcps_rcvduppack; /* duplicate-only packets received */ 547 u_quad_t tcps_rcvdupbyte; /* duplicate-only bytes received */ 548 u_quad_t tcps_rcvpartduppack; /* packets with some duplicate data */ 549 u_quad_t tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */ 550 u_quad_t tcps_rcvoopack; /* out-of-order packets received */ 551 u_quad_t tcps_rcvoobyte; /* out-of-order bytes received */ 552 u_quad_t tcps_rcvpackafterwin; /* packets with data after window */ 553 u_quad_t tcps_rcvbyteafterwin; /* bytes rcvd after window */ 554 u_quad_t tcps_rcvafterclose; /* packets rcvd after "close" */ 555 u_quad_t tcps_rcvwinprobe; /* rcvd window probe packets */ 556 u_quad_t tcps_rcvdupack; /* rcvd duplicate acks */ 557 u_quad_t tcps_rcvacktoomuch; /* rcvd acks for unsent data */ 558 u_quad_t tcps_rcvackpack; /* rcvd ack packets */ 559 u_quad_t tcps_rcvackbyte; /* bytes acked by rcvd acks */ 560 u_quad_t tcps_rcvwinupd; /* rcvd window update packets */ 561 u_quad_t tcps_pawsdrop; /* segments dropped due to PAWS */ 562 u_quad_t tcps_predack; /* times hdr predict ok for acks */ 563 u_quad_t tcps_preddat; /* times hdr predict ok for data pkts */ 564 565 u_quad_t tcps_pcbhashmiss; /* input packets missing pcb hash */ 566 u_quad_t tcps_noport; /* no socket on port */ 567 u_quad_t tcps_badsyn; /* received ack for which we have 568 no SYN in compressed state */ 569 u_quad_t tcps_delayed_free; /* delayed pool_put() of tcpcb */ 570 571 /* These statistics deal with the SYN cache. */ 572 u_quad_t tcps_sc_added; /* # of entries added */ 573 u_quad_t tcps_sc_completed; /* # of connections completed */ 574 u_quad_t tcps_sc_timed_out; /* # of entries timed out */ 575 u_quad_t tcps_sc_overflowed; /* # dropped due to overflow */ 576 u_quad_t tcps_sc_reset; /* # dropped due to RST */ 577 u_quad_t tcps_sc_unreach; /* # dropped due to ICMP unreach */ 578 u_quad_t tcps_sc_bucketoverflow;/* # dropped due to bucket overflow */ 579 u_quad_t tcps_sc_aborted; /* # of entries aborted (no mem) */ 580 u_quad_t tcps_sc_dupesyn; /* # of duplicate SYNs received */ 581 u_quad_t tcps_sc_dropped; /* # of SYNs dropped (no route/mem) */ 582 u_quad_t tcps_sc_collisions; /* # of hash collisions */ 583 u_quad_t tcps_sc_retransmitted; /* # of retransmissions */ 584 u_quad_t tcps_sc_delayed_free; /* # of delayed pool_put()s */ 585 586 u_quad_t tcps_selfquench; /* # of ENOBUFS we get on output */ 587 u_quad_t tcps_badsig; /* # of drops due to bad signature */ 588 u_quad_t tcps_goodsig; /* # of packets with good signature */ 589 }; 590 591 /* 592 * Names for TCP sysctl objects. 593 */ 594 #define TCPCTL_RFC1323 1 /* RFC1323 timestamps/scaling */ 595 #define TCPCTL_SENDSPACE 2 /* default send buffer */ 596 #define TCPCTL_RECVSPACE 3 /* default recv buffer */ 597 #define TCPCTL_MSSDFLT 4 /* default seg size */ 598 #define TCPCTL_SYN_CACHE_LIMIT 5 /* max size of comp. state engine */ 599 #define TCPCTL_SYN_BUCKET_LIMIT 6 /* max size of hash bucket */ 600 #if 0 /*obsoleted*/ 601 #define TCPCTL_SYN_CACHE_INTER 7 /* interval of comp. state timer */ 602 #endif 603 #define TCPCTL_INIT_WIN 8 /* initial window */ 604 #define TCPCTL_MSS_IFMTU 9 /* mss from interface, not in_maxmtu */ 605 #define TCPCTL_SACK 10 /* RFC2018 selective acknowledgement */ 606 #define TCPCTL_WSCALE 11 /* RFC1323 window scaling */ 607 #define TCPCTL_TSTAMP 12 /* RFC1323 timestamps */ 608 #define TCPCTL_COMPAT_42 13 /* 4.2BSD TCP bug work-arounds */ 609 #define TCPCTL_CWM 14 /* Congestion Window Monitoring */ 610 #define TCPCTL_CWM_BURSTSIZE 15 /* burst size allowed by CWM */ 611 #define TCPCTL_ACK_ON_PUSH 16 /* ACK immediately on PUSH */ 612 #define TCPCTL_KEEPIDLE 17 /* keepalive idle time */ 613 #define TCPCTL_KEEPINTVL 18 /* keepalive probe interval */ 614 #define TCPCTL_KEEPCNT 19 /* keepalive count */ 615 #define TCPCTL_SLOWHZ 20 /* PR_SLOWHZ (read-only) */ 616 #define TCPCTL_NEWRENO 21 /* NewReno Congestion Control */ 617 #define TCPCTL_LOG_REFUSED 22 /* Log refused connections */ 618 #if 0 /*obsoleted*/ 619 #define TCPCTL_RSTRATELIMIT 23 /* RST rate limit */ 620 #endif 621 #define TCPCTL_RSTPPSLIMIT 24 /* RST pps limit */ 622 #define TCPCTL_DELACK_TICKS 25 /* # ticks to delay ACK */ 623 #define TCPCTL_INIT_WIN_LOCAL 26 /* initial window for local nets */ 624 #define TCPCTL_IDENT 27 /* rfc 931 identd */ 625 #define TCPCTL_ACKDROPRATELIMIT 28 /* SYN/RST -> ACK rate limit */ 626 #define TCPCTL_LOOPBACKCKSUM 29 /* do TCP checksum on loopback */ 627 #define TCPCTL_MAXID 30 628 629 #define TCPCTL_NAMES { \ 630 { 0, 0 }, \ 631 { "rfc1323", CTLTYPE_INT }, \ 632 { "sendspace", CTLTYPE_INT }, \ 633 { "recvspace", CTLTYPE_INT }, \ 634 { "mssdflt", CTLTYPE_INT }, \ 635 { "syn_cache_limit", CTLTYPE_INT }, \ 636 { "syn_bucket_limit", CTLTYPE_INT }, \ 637 { 0, 0 },\ 638 { "init_win", CTLTYPE_INT }, \ 639 { "mss_ifmtu", CTLTYPE_INT }, \ 640 { "sack", CTLTYPE_INT }, \ 641 { "win_scale", CTLTYPE_INT }, \ 642 { "timestamps", CTLTYPE_INT }, \ 643 { "compat_42", CTLTYPE_INT }, \ 644 { "cwm", CTLTYPE_INT }, \ 645 { "cwm_burstsize", CTLTYPE_INT }, \ 646 { "ack_on_push", CTLTYPE_INT }, \ 647 { "keepidle", CTLTYPE_INT }, \ 648 { "keepintvl", CTLTYPE_INT }, \ 649 { "keepcnt", CTLTYPE_INT }, \ 650 { "slowhz", CTLTYPE_INT }, \ 651 { "newreno", CTLTYPE_INT }, \ 652 { "log_refused",CTLTYPE_INT }, \ 653 { 0, 0 }, \ 654 { "rstppslimit", CTLTYPE_INT }, \ 655 { "delack_ticks", CTLTYPE_INT }, \ 656 { "init_win_local", CTLTYPE_INT }, \ 657 { "ident", CTLTYPE_STRUCT }, \ 658 { "ackdropppslimit", CTLTYPE_INT }, \ 659 { "do_loopback_cksum", CTLTYPE_INT }, \ 660 } 661 662 #ifdef _KERNEL 663 extern struct inpcbtable tcbtable; /* head of queue of active tcpcb's */ 664 extern struct tcpstat tcpstat; /* tcp statistics */ 665 extern u_int32_t tcp_now; /* for RFC 1323 timestamps */ 666 extern int tcp_do_rfc1323; /* enabled/disabled? */ 667 extern int tcp_do_sack; /* SACK enabled/disabled? */ 668 extern int tcp_do_win_scale; /* RFC1323 window scaling enabled/disabled? */ 669 extern int tcp_do_timestamps; /* RFC1323 timestamps enabled/disabled? */ 670 extern int tcp_do_newreno; /* Use the New Reno algorithms */ 671 extern int tcp_mssdflt; /* default seg size */ 672 extern int tcp_init_win; /* initial window */ 673 extern int tcp_init_win_local; /* initial window for local nets */ 674 extern int tcp_mss_ifmtu; /* take MSS from interface, not in_maxmtu */ 675 extern int tcp_compat_42; /* work around ancient broken TCP peers */ 676 extern int tcp_cwm; /* enable Congestion Window Monitoring */ 677 extern int tcp_cwm_burstsize; /* burst size allowed by CWM */ 678 extern int tcp_ack_on_push; /* ACK immediately on PUSH */ 679 extern int tcp_syn_cache_limit; /* max entries for compressed state engine */ 680 extern int tcp_syn_bucket_limit;/* max entries per hash bucket */ 681 extern int tcp_log_refused; /* log refused connections */ 682 extern int tcp_do_loopback_cksum;/* do TCP checksum on loopback? */ 683 684 extern int tcp_rst_ppslim; 685 extern int tcp_ackdrop_ppslim; 686 687 extern int tcp_syn_cache_size; 688 extern struct syn_cache_head tcp_syn_cache[]; 689 extern u_long syn_cache_count; 690 691 extern struct pool tcpipqent_pool; 692 693 #ifdef MBUFTRACE 694 extern struct mowner tcp_rx_mowner; 695 extern struct mowner tcp_tx_mowner; 696 extern struct mowner tcp_mowner; 697 #endif 698 699 #define TCPCTL_VARIABLES { \ 700 { 0 }, \ 701 { 1, 0, &tcp_do_rfc1323 }, \ 702 { 1, 0, &tcp_sendspace }, \ 703 { 1, 0, &tcp_recvspace }, \ 704 { 1, 0, &tcp_mssdflt }, \ 705 { 1, 0, &tcp_syn_cache_limit }, \ 706 { 1, 0, &tcp_syn_bucket_limit }, \ 707 { 0 }, \ 708 { 1, 0, &tcp_init_win }, \ 709 { 1, 0, &tcp_mss_ifmtu }, \ 710 { 1, 0, &tcp_do_sack }, \ 711 { 1, 0, &tcp_do_win_scale }, \ 712 { 1, 0, &tcp_do_timestamps }, \ 713 { 1, 0, &tcp_compat_42 }, \ 714 { 1, 0, &tcp_cwm }, \ 715 { 1, 0, &tcp_cwm_burstsize }, \ 716 { 1, 0, &tcp_ack_on_push }, \ 717 { 1, 0, &tcp_keepidle }, \ 718 { 1, 0, &tcp_keepintvl }, \ 719 { 1, 0, &tcp_keepcnt }, \ 720 { 1, 1, 0, PR_SLOWHZ }, \ 721 { 1, 0, &tcp_do_newreno }, \ 722 { 1, 0, &tcp_log_refused }, \ 723 { 0 }, \ 724 { 1, 0, &tcp_rst_ppslim }, \ 725 { 1, 0, &tcp_delack_ticks }, \ 726 { 1, 0, &tcp_init_win_local }, \ 727 { 1, 0, &tcp_ackdrop_ppslim }, \ 728 } 729 730 #ifdef __NO_STRICT_ALIGNMENT 731 #define TCP_HDR_ALIGNED_P(th) 1 732 #else 733 #define TCP_HDR_ALIGNED_P(th) ((((vaddr_t)(th)) & 3) == 0) 734 #endif 735 736 struct secasvar; 737 738 int tcp_attach(struct socket *); 739 void tcp_canceltimers(struct tcpcb *); 740 int tcp_timers_invoking(struct tcpcb*); 741 struct tcpcb * 742 tcp_close(struct tcpcb *); 743 int tcp_isdead(struct tcpcb *); 744 #ifdef INET6 745 void tcp6_ctlinput(int, struct sockaddr *, void *); 746 #endif 747 void *tcp_ctlinput(int, struct sockaddr *, void *); 748 int tcp_ctloutput(int, struct socket *, int, int, struct mbuf **); 749 struct tcpcb * 750 tcp_disconnect(struct tcpcb *); 751 struct tcpcb * 752 tcp_drop(struct tcpcb *, int); 753 #ifdef TCP_SIGNATURE 754 int tcp_signature_apply(void *, caddr_t, u_int); 755 struct secasvar *tcp_signature_getsav(struct mbuf *, struct tcphdr *); 756 int tcp_signature(struct mbuf *, struct tcphdr *, int, struct secasvar *, 757 char *); 758 #endif 759 int tcp_dooptions(struct tcpcb *, u_char *, int, struct tcphdr *, 760 struct mbuf *, int, struct tcp_opt_info *); 761 void tcp_drain(void); 762 void tcp_established(struct tcpcb *); 763 void tcp_init(void); 764 #ifdef INET6 765 int tcp6_input(struct mbuf **, int *, int); 766 #endif 767 void tcp_input(struct mbuf *, ...); 768 u_long tcp_mss_to_advertise(const struct ifnet *, int); 769 void tcp_mss_from_peer(struct tcpcb *, int); 770 void tcp_tcpcb_template(void); 771 struct tcpcb * 772 tcp_newtcpcb(int, void *); 773 void tcp_notify(struct inpcb *, int); 774 #ifdef INET6 775 void tcp6_notify(struct in6pcb *, int); 776 #endif 777 u_int tcp_optlen(struct tcpcb *); 778 int tcp_output(struct tcpcb *); 779 void tcp_pulloutofband(struct socket *, 780 struct tcphdr *, struct mbuf *, int); 781 void tcp_quench(struct inpcb *, int); 782 #ifdef INET6 783 void tcp6_quench(struct in6pcb *, int); 784 #endif 785 int tcp_reass(struct tcpcb *, struct tcphdr *, struct mbuf *, int *); 786 int tcp_respond(struct tcpcb *, struct mbuf *, struct mbuf *, 787 struct tcphdr *, tcp_seq, tcp_seq, int); 788 void tcp_rmx_rtt(struct tcpcb *); 789 void tcp_setpersist(struct tcpcb *); 790 #ifdef TCP_SIGNATURE 791 int tcp_signature_compute(struct mbuf *, struct tcphdr *, int, int, 792 int, u_char *, u_int); 793 #endif 794 void tcp_slowtimo(void); 795 struct mbuf * 796 tcp_template(struct tcpcb *); 797 void tcp_trace(int, int, struct tcpcb *, struct mbuf *, int); 798 struct tcpcb * 799 tcp_usrclosed(struct tcpcb *); 800 int tcp_sysctl(int *, u_int, void *, size_t *, void *, size_t); 801 int tcp_usrreq(struct socket *, 802 int, struct mbuf *, struct mbuf *, struct mbuf *, struct proc *); 803 void tcp_xmit_timer(struct tcpcb *, uint32_t); 804 tcp_seq tcp_new_iss(struct tcpcb *, tcp_seq); 805 tcp_seq tcp_new_iss1(void *, void *, u_int16_t, u_int16_t, size_t, 806 tcp_seq); 807 808 int syn_cache_add(struct sockaddr *, struct sockaddr *, 809 struct tcphdr *, unsigned int, struct socket *, 810 struct mbuf *, u_char *, int, struct tcp_opt_info *); 811 void syn_cache_unreach(struct sockaddr *, struct sockaddr *, 812 struct tcphdr *); 813 struct socket *syn_cache_get(struct sockaddr *, struct sockaddr *, 814 struct tcphdr *, unsigned int, unsigned int, 815 struct socket *so, struct mbuf *); 816 void syn_cache_init(void); 817 void syn_cache_insert(struct syn_cache *, struct tcpcb *); 818 struct syn_cache *syn_cache_lookup(struct sockaddr *, struct sockaddr *, 819 struct syn_cache_head **); 820 void syn_cache_reset(struct sockaddr *, struct sockaddr *, 821 struct tcphdr *); 822 int syn_cache_respond(struct syn_cache *, struct mbuf *); 823 void syn_cache_timer(void *); 824 void syn_cache_cleanup(struct tcpcb *); 825 826 void tcp_newreno(struct tcpcb *, struct tcphdr *); 827 828 int tcp_input_checksum(int, struct mbuf *, const struct tcphdr *, int, int, 829 int); 830 #endif 831 832 #endif /* _NETINET_TCP_VAR_H_ */ 833
Indexes created Sun Sep 28 12:09:53 GMT 2025