1 /* $NetBSD: tcp_var.h,v 1.118 2005/02/06 20:13:09 pk 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 short t_partialacks; /* partials acks during fast rexmit */ 181 u_short t_peermss; /* peer's maximum segment size */ 182 u_short t_ourmss; /* our's maximum segment size */ 183 u_short t_segsz; /* current segment size in use */ 184 char t_force; /* 1 if forcing out a byte */ 185 u_int t_flags; 186 #define TF_ACKNOW 0x0001 /* ack peer immediately */ 187 #define TF_DELACK 0x0002 /* ack, but try to delay it */ 188 #define TF_NODELAY 0x0004 /* don't delay packets to coalesce */ 189 #define TF_NOOPT 0x0008 /* don't use tcp options */ 190 #define TF_REQ_SCALE 0x0020 /* have/will request window scaling */ 191 #define TF_RCVD_SCALE 0x0040 /* other side has requested scaling */ 192 #define TF_REQ_TSTMP 0x0080 /* have/will request timestamps */ 193 #define TF_RCVD_TSTMP 0x0100 /* a timestamp was received in SYN */ 194 #define TF_SACK_PERMIT 0x0200 /* other side said I could SACK */ 195 #define TF_SYN_REXMT 0x0400 /* rexmit timer fired on SYN */ 196 #define TF_WILL_SACK 0x0800 /* try to use SACK */ 197 #define TF_CANT_TXSACK 0x1000 /* other side said I could not SACK */ 198 #define TF_IGNR_RXSACK 0x2000 /* ignore received SACK blocks */ 199 #define TF_REASSEMBLING 0x4000 /* we're busy reassembling */ 200 #define TF_DEAD 0x8000 /* dead and to-be-released */ 201 #define TF_SIGNATURE 0x400000 /* require MD5 digests (RFC2385) */ 202 203 204 struct mbuf *t_template; /* skeletal packet for transmit */ 205 struct inpcb *t_inpcb; /* back pointer to internet pcb */ 206 struct in6pcb *t_in6pcb; /* back pointer to internet pcb */ 207 struct callout t_delack_ch; /* delayed ACK callout */ 208 /* 209 * The following fields are used as in the protocol specification. 210 * See RFC783, Dec. 1981, page 21. 211 */ 212 /* send sequence variables */ 213 tcp_seq snd_una; /* send unacknowledged */ 214 tcp_seq snd_nxt; /* send next */ 215 tcp_seq snd_up; /* send urgent pointer */ 216 tcp_seq snd_wl1; /* window update seg seq number */ 217 tcp_seq snd_wl2; /* window update seg ack number */ 218 tcp_seq iss; /* initial send sequence number */ 219 u_long snd_wnd; /* send window */ 220 tcp_seq snd_recover; /* for use in fast recovery */ 221 tcp_seq snd_high; /* NewReno false fast rexmit seq */ 222 /* receive sequence variables */ 223 u_long rcv_wnd; /* receive window */ 224 tcp_seq rcv_nxt; /* receive next */ 225 tcp_seq rcv_up; /* receive urgent pointer */ 226 tcp_seq irs; /* initial receive sequence number */ 227 /* 228 * Additional variables for this implementation. 229 */ 230 /* receive variables */ 231 tcp_seq rcv_adv; /* advertised window */ 232 /* retransmit variables */ 233 tcp_seq snd_max; /* highest sequence number sent; 234 * used to recognize retransmits 235 */ 236 /* congestion control (for slow start, source quench, retransmit after loss) */ 237 u_long snd_cwnd; /* congestion-controlled window */ 238 u_long snd_ssthresh; /* snd_cwnd size threshhold for 239 * for slow start exponential to 240 * linear switch 241 */ 242 /* 243 * transmit timing stuff. See below for scale of srtt and rttvar. 244 * "Variance" is actually smoothed difference. 245 */ 246 uint32_t t_rcvtime; /* time last segment received */ 247 uint32_t t_rtttime; /* time we started measuring rtt */ 248 tcp_seq t_rtseq; /* sequence number being timed */ 249 int32_t t_srtt; /* smoothed round-trip time */ 250 int32_t t_rttvar; /* variance in round-trip time */ 251 uint32_t t_rttmin; /* minimum rtt allowed */ 252 u_long max_sndwnd; /* largest window peer has offered */ 253 254 /* out-of-band data */ 255 char t_oobflags; /* have some */ 256 char t_iobc; /* input character */ 257 #define TCPOOB_HAVEDATA 0x01 258 #define TCPOOB_HADDATA 0x02 259 short t_softerror; /* possible error not yet reported */ 260 261 /* RFC 1323 variables */ 262 u_char snd_scale; /* window scaling for send window */ 263 u_char rcv_scale; /* window scaling for recv window */ 264 u_char request_r_scale; /* pending window scaling */ 265 u_char requested_s_scale; 266 u_int32_t ts_recent; /* timestamp echo data */ 267 u_int32_t ts_recent_age; /* when last updated */ 268 u_int32_t ts_timebase; /* our timebase */ 269 tcp_seq last_ack_sent; 270 271 /* SACK stuff */ 272 struct ipqehead timeq; /* time sequenced queue (for SACK) */ 273 274 /* path MTU discovery blackhole detection */ 275 int t_mtudisc; /* perform mtudisc for this tcb */ 276 277 /* pointer for syn cache entries*/ 278 LIST_HEAD(, syn_cache) t_sc; /* list of entries by this tcb */ 279 280 /* prediction of next mbuf when using large window sizes */ 281 struct mbuf *t_lastm; /* last mbuf that data was sent from */ 282 int t_inoff; /* data offset in previous mbuf */ 283 int t_lastoff; /* last data address in mbuf chain */ 284 int t_lastlen; /* last length read from mbuf chain */ 285 }; 286 287 #ifdef _KERNEL 288 /* 289 * TCP reassembly queue locks. 290 */ 291 static __inline int tcp_reass_lock_try (struct tcpcb *) 292 __attribute__((__unused__)); 293 static __inline void tcp_reass_unlock (struct tcpcb *) 294 __attribute__((__unused__)); 295 296 static __inline int 297 tcp_reass_lock_try(tp) 298 struct tcpcb *tp; 299 { 300 int s; 301 302 /* 303 * Use splvm() -- we're blocking things that would cause 304 * mbuf allocation. 305 */ 306 s = splvm(); 307 if (tp->t_flags & TF_REASSEMBLING) { 308 splx(s); 309 return (0); 310 } 311 tp->t_flags |= TF_REASSEMBLING; 312 splx(s); 313 return (1); 314 } 315 316 static __inline void 317 tcp_reass_unlock(tp) 318 struct tcpcb *tp; 319 { 320 int s; 321 322 s = splvm(); 323 tp->t_flags &= ~TF_REASSEMBLING; 324 splx(s); 325 } 326 327 #ifdef DIAGNOSTIC 328 #define TCP_REASS_LOCK(tp) \ 329 do { \ 330 if (tcp_reass_lock_try(tp) == 0) { \ 331 printf("%s:%d: tcpcb %p reass already locked\n", \ 332 __FILE__, __LINE__, tp); \ 333 panic("tcp_reass_lock"); \ 334 } \ 335 } while (/*CONSTCOND*/ 0) 336 #define TCP_REASS_LOCK_CHECK(tp) \ 337 do { \ 338 if (((tp)->t_flags & TF_REASSEMBLING) == 0) { \ 339 printf("%s:%d: tcpcb %p reass lock not held\n", \ 340 __FILE__, __LINE__, tp); \ 341 panic("tcp reass lock check"); \ 342 } \ 343 } while (/*CONSTCOND*/ 0) 344 #else 345 #define TCP_REASS_LOCK(tp) (void) tcp_reass_lock_try((tp)) 346 #define TCP_REASS_LOCK_CHECK(tp) /* nothing */ 347 #endif 348 349 #define TCP_REASS_UNLOCK(tp) tcp_reass_unlock((tp)) 350 #endif /* _KERNEL */ 351 352 /* 353 * Queue for delayed ACK processing. 354 */ 355 #ifdef _KERNEL 356 extern int tcp_delack_ticks; 357 void tcp_delack(void *); 358 359 #define TCP_RESTART_DELACK(tp) \ 360 callout_reset(&(tp)->t_delack_ch, tcp_delack_ticks, \ 361 tcp_delack, tp) 362 363 #define TCP_SET_DELACK(tp) \ 364 do { \ 365 if (((tp)->t_flags & TF_DELACK) == 0) { \ 366 (tp)->t_flags |= TF_DELACK; \ 367 TCP_RESTART_DELACK(tp); \ 368 } \ 369 } while (/*CONSTCOND*/0) 370 371 #define TCP_CLEAR_DELACK(tp) \ 372 do { \ 373 if ((tp)->t_flags & TF_DELACK) { \ 374 (tp)->t_flags &= ~TF_DELACK; \ 375 callout_stop(&(tp)->t_delack_ch); \ 376 } \ 377 } while (/*CONSTCOND*/0) 378 #endif /* _KERNEL */ 379 380 /* 381 * Compute the current timestamp for a connection. 382 */ 383 #define TCP_TIMESTAMP(tp) (tcp_now - (tp)->ts_timebase) 384 385 /* 386 * Handy way of passing around TCP option info. 387 */ 388 struct tcp_opt_info { 389 int ts_present; 390 u_int32_t ts_val; 391 u_int32_t ts_ecr; 392 u_int16_t maxseg; 393 }; 394 395 #define TOF_SIGNATURE 0x0040 /* signature option present */ 396 #define TOF_SIGLEN 0x0080 /* sigature length valid (RFC2385) */ 397 398 /* 399 * Data for the TCP compressed state engine. 400 */ 401 union syn_cache_sa { 402 struct sockaddr sa; 403 struct sockaddr_in sin; 404 #if 1 /*def INET6*/ 405 struct sockaddr_in6 sin6; 406 #endif 407 }; 408 409 struct syn_cache { 410 TAILQ_ENTRY(syn_cache) sc_bucketq; /* link on bucket list */ 411 struct callout sc_timer; /* rexmt timer */ 412 union { /* cached route */ 413 struct route route4; 414 #ifdef INET6 415 struct route_in6 route6; 416 #endif 417 } sc_route_u; 418 #define sc_route4 sc_route_u.route4 419 #ifdef INET6 420 #define sc_route6 sc_route_u.route6 421 #endif 422 long sc_win; /* advertised window */ 423 int sc_bucketidx; /* our bucket index */ 424 u_int32_t sc_hash; 425 u_int32_t sc_timestamp; /* timestamp from SYN */ 426 u_int32_t sc_timebase; /* our local timebase */ 427 union syn_cache_sa sc_src; 428 union syn_cache_sa sc_dst; 429 tcp_seq sc_irs; 430 tcp_seq sc_iss; 431 u_int sc_rxtcur; /* current rxt timeout */ 432 u_int sc_rxttot; /* total time spend on queues */ 433 u_short sc_rxtshift; /* for computing backoff */ 434 u_short sc_flags; 435 436 #define SCF_UNREACH 0x0001 /* we've had an unreach error */ 437 #define SCF_TIMESTAMP 0x0002 /* peer will do timestamps */ 438 #define SCF_DEAD 0x0004 /* this entry to be released */ 439 #define SCF_SIGNATURE 0x40 /* send MD5 digests */ 440 441 struct mbuf *sc_ipopts; /* IP options */ 442 u_int16_t sc_peermaxseg; 443 u_int16_t sc_ourmaxseg; 444 u_int8_t sc_request_r_scale : 4, 445 sc_requested_s_scale : 4; 446 447 struct tcpcb *sc_tp; /* tcb for listening socket */ 448 LIST_ENTRY(syn_cache) sc_tpq; /* list of entries by same tp */ 449 }; 450 451 struct syn_cache_head { 452 TAILQ_HEAD(, syn_cache) sch_bucket; /* bucket entries */ 453 u_short sch_length; /* # entries in bucket */ 454 }; 455 456 #define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb) 457 #ifdef INET6 458 #define in6totcpcb(ip) ((struct tcpcb *)(ip)->in6p_ppcb) 459 #endif 460 #ifndef INET6 461 #define sototcpcb(so) (intotcpcb(sotoinpcb(so))) 462 #else 463 #define sototcpcb(so) (((so)->so_proto->pr_domain->dom_family == AF_INET) \ 464 ? intotcpcb(sotoinpcb(so)) \ 465 : in6totcpcb(sotoin6pcb(so))) 466 #endif 467 468 /* 469 * The smoothed round-trip time and estimated variance 470 * are stored as fixed point numbers scaled by the values below. 471 * For convenience, these scales are also used in smoothing the average 472 * (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed). 473 * With these scales, srtt has 3 bits to the right of the binary point, 474 * and thus an "ALPHA" of 0.875. rttvar has 2 bits to the right of the 475 * binary point, and is smoothed with an ALPHA of 0.75. 476 */ 477 #define TCP_RTT_SHIFT 3 /* shift for srtt; 3 bits frac. */ 478 #define TCP_RTTVAR_SHIFT 2 /* multiplier for rttvar; 2 bits */ 479 480 /* 481 * The initial retransmission should happen at rtt + 4 * rttvar. 482 * Because of the way we do the smoothing, srtt and rttvar 483 * will each average +1/2 tick of bias. When we compute 484 * the retransmit timer, we want 1/2 tick of rounding and 485 * 1 extra tick because of +-1/2 tick uncertainty in the 486 * firing of the timer. The bias will give us exactly the 487 * 1.5 tick we need. But, because the bias is 488 * statistical, we have to test that we don't drop below 489 * the minimum feasible timer (which is 2 ticks). 490 * This macro assumes that the value of 1<<TCP_RTTVAR_SHIFT 491 * is the same as the multiplier for rttvar. 492 */ 493 #define TCP_REXMTVAL(tp) \ 494 ((((tp)->t_srtt >> TCP_RTT_SHIFT) + (tp)->t_rttvar) >> 2) 495 496 /* 497 * Compute the initial window for slow start. 498 */ 499 #define TCP_INITIAL_WINDOW(iw, segsz) \ 500 (((iw) == 0) ? (min(4 * (segsz), max(2 * (segsz), 4380))) : \ 501 ((segsz) * (iw))) 502 503 /* 504 * TCP statistics. 505 * Many of these should be kept per connection, 506 * but that's inconvenient at the moment. 507 */ 508 struct tcpstat { 509 u_quad_t tcps_connattempt; /* connections initiated */ 510 u_quad_t tcps_accepts; /* connections accepted */ 511 u_quad_t tcps_connects; /* connections established */ 512 u_quad_t tcps_drops; /* connections dropped */ 513 u_quad_t tcps_conndrops; /* embryonic connections dropped */ 514 u_quad_t tcps_closed; /* conn. closed (includes drops) */ 515 u_quad_t tcps_segstimed; /* segs where we tried to get rtt */ 516 u_quad_t tcps_rttupdated; /* times we succeeded */ 517 u_quad_t tcps_delack; /* delayed acks sent */ 518 u_quad_t tcps_timeoutdrop; /* conn. dropped in rxmt timeout */ 519 u_quad_t tcps_rexmttimeo; /* retransmit timeouts */ 520 u_quad_t tcps_persisttimeo; /* persist timeouts */ 521 u_quad_t tcps_keeptimeo; /* keepalive timeouts */ 522 u_quad_t tcps_keepprobe; /* keepalive probes sent */ 523 u_quad_t tcps_keepdrops; /* connections dropped in keepalive */ 524 u_quad_t tcps_persistdrops; /* connections dropped in persist */ 525 u_quad_t tcps_connsdrained; /* connections drained due to memory 526 shortage */ 527 u_quad_t tcps_pmtublackhole; /* PMTUD blackhole detected */ 528 529 u_quad_t tcps_sndtotal; /* total packets sent */ 530 u_quad_t tcps_sndpack; /* data packets sent */ 531 u_quad_t tcps_sndbyte; /* data bytes sent */ 532 u_quad_t tcps_sndrexmitpack; /* data packets retransmitted */ 533 u_quad_t tcps_sndrexmitbyte; /* data bytes retransmitted */ 534 u_quad_t tcps_sndacks; /* ack-only packets sent */ 535 u_quad_t tcps_sndprobe; /* window probes sent */ 536 u_quad_t tcps_sndurg; /* packets sent with URG only */ 537 u_quad_t tcps_sndwinup; /* window update-only packets sent */ 538 u_quad_t tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */ 539 540 u_quad_t tcps_rcvtotal; /* total packets received */ 541 u_quad_t tcps_rcvpack; /* packets received in sequence */ 542 u_quad_t tcps_rcvbyte; /* bytes received in sequence */ 543 u_quad_t tcps_rcvbadsum; /* packets received with ccksum errs */ 544 u_quad_t tcps_rcvbadoff; /* packets received with bad offset */ 545 u_quad_t tcps_rcvmemdrop; /* packets dropped for lack of memory */ 546 u_quad_t tcps_rcvshort; /* packets received too short */ 547 u_quad_t tcps_rcvduppack; /* duplicate-only packets received */ 548 u_quad_t tcps_rcvdupbyte; /* duplicate-only bytes received */ 549 u_quad_t tcps_rcvpartduppack; /* packets with some duplicate data */ 550 u_quad_t tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */ 551 u_quad_t tcps_rcvoopack; /* out-of-order packets received */ 552 u_quad_t tcps_rcvoobyte; /* out-of-order bytes received */ 553 u_quad_t tcps_rcvpackafterwin; /* packets with data after window */ 554 u_quad_t tcps_rcvbyteafterwin; /* bytes rcvd after window */ 555 u_quad_t tcps_rcvafterclose; /* packets rcvd after "close" */ 556 u_quad_t tcps_rcvwinprobe; /* rcvd window probe packets */ 557 u_quad_t tcps_rcvdupack; /* rcvd duplicate acks */ 558 u_quad_t tcps_rcvacktoomuch; /* rcvd acks for unsent data */ 559 u_quad_t tcps_rcvackpack; /* rcvd ack packets */ 560 u_quad_t tcps_rcvackbyte; /* bytes acked by rcvd acks */ 561 u_quad_t tcps_rcvwinupd; /* rcvd window update packets */ 562 u_quad_t tcps_pawsdrop; /* segments dropped due to PAWS */ 563 u_quad_t tcps_predack; /* times hdr predict ok for acks */ 564 u_quad_t tcps_preddat; /* times hdr predict ok for data pkts */ 565 566 u_quad_t tcps_pcbhashmiss; /* input packets missing pcb hash */ 567 u_quad_t tcps_noport; /* no socket on port */ 568 u_quad_t tcps_badsyn; /* received ack for which we have 569 no SYN in compressed state */ 570 u_quad_t tcps_delayed_free; /* delayed pool_put() of tcpcb */ 571 572 /* These statistics deal with the SYN cache. */ 573 u_quad_t tcps_sc_added; /* # of entries added */ 574 u_quad_t tcps_sc_completed; /* # of connections completed */ 575 u_quad_t tcps_sc_timed_out; /* # of entries timed out */ 576 u_quad_t tcps_sc_overflowed; /* # dropped due to overflow */ 577 u_quad_t tcps_sc_reset; /* # dropped due to RST */ 578 u_quad_t tcps_sc_unreach; /* # dropped due to ICMP unreach */ 579 u_quad_t tcps_sc_bucketoverflow;/* # dropped due to bucket overflow */ 580 u_quad_t tcps_sc_aborted; /* # of entries aborted (no mem) */ 581 u_quad_t tcps_sc_dupesyn; /* # of duplicate SYNs received */ 582 u_quad_t tcps_sc_dropped; /* # of SYNs dropped (no route/mem) */ 583 u_quad_t tcps_sc_collisions; /* # of hash collisions */ 584 u_quad_t tcps_sc_retransmitted; /* # of retransmissions */ 585 u_quad_t tcps_sc_delayed_free; /* # of delayed pool_put()s */ 586 587 u_quad_t tcps_selfquench; /* # of ENOBUFS we get on output */ 588 u_quad_t tcps_badsig; /* # of drops due to bad signature */ 589 u_quad_t tcps_goodsig; /* # of packets with good signature */ 590 }; 591 592 /* 593 * Names for TCP sysctl objects. 594 */ 595 #define TCPCTL_RFC1323 1 /* RFC1323 timestamps/scaling */ 596 #define TCPCTL_SENDSPACE 2 /* default send buffer */ 597 #define TCPCTL_RECVSPACE 3 /* default recv buffer */ 598 #define TCPCTL_MSSDFLT 4 /* default seg size */ 599 #define TCPCTL_SYN_CACHE_LIMIT 5 /* max size of comp. state engine */ 600 #define TCPCTL_SYN_BUCKET_LIMIT 6 /* max size of hash bucket */ 601 #if 0 /*obsoleted*/ 602 #define TCPCTL_SYN_CACHE_INTER 7 /* interval of comp. state timer */ 603 #endif 604 #define TCPCTL_INIT_WIN 8 /* initial window */ 605 #define TCPCTL_MSS_IFMTU 9 /* mss from interface, not in_maxmtu */ 606 #define TCPCTL_SACK 10 /* RFC2018 selective acknowledgement */ 607 #define TCPCTL_WSCALE 11 /* RFC1323 window scaling */ 608 #define TCPCTL_TSTAMP 12 /* RFC1323 timestamps */ 609 #define TCPCTL_COMPAT_42 13 /* 4.2BSD TCP bug work-arounds */ 610 #define TCPCTL_CWM 14 /* Congestion Window Monitoring */ 611 #define TCPCTL_CWM_BURSTSIZE 15 /* burst size allowed by CWM */ 612 #define TCPCTL_ACK_ON_PUSH 16 /* ACK immediately on PUSH */ 613 #define TCPCTL_KEEPIDLE 17 /* keepalive idle time */ 614 #define TCPCTL_KEEPINTVL 18 /* keepalive probe interval */ 615 #define TCPCTL_KEEPCNT 19 /* keepalive count */ 616 #define TCPCTL_SLOWHZ 20 /* PR_SLOWHZ (read-only) */ 617 #define TCPCTL_NEWRENO 21 /* NewReno Congestion Control */ 618 #define TCPCTL_LOG_REFUSED 22 /* Log refused connections */ 619 #if 0 /*obsoleted*/ 620 #define TCPCTL_RSTRATELIMIT 23 /* RST rate limit */ 621 #endif 622 #define TCPCTL_RSTPPSLIMIT 24 /* RST pps limit */ 623 #define TCPCTL_DELACK_TICKS 25 /* # ticks to delay ACK */ 624 #define TCPCTL_INIT_WIN_LOCAL 26 /* initial window for local nets */ 625 #define TCPCTL_IDENT 27 /* rfc 931 identd */ 626 #define TCPCTL_ACKDROPRATELIMIT 28 /* SYN/RST -> ACK rate limit */ 627 #define TCPCTL_LOOPBACKCKSUM 29 /* do TCP checksum on loopback */ 628 #define TCPCTL_MAXID 30 629 630 #define TCPCTL_NAMES { \ 631 { 0, 0 }, \ 632 { "rfc1323", CTLTYPE_INT }, \ 633 { "sendspace", CTLTYPE_INT }, \ 634 { "recvspace", CTLTYPE_INT }, \ 635 { "mssdflt", CTLTYPE_INT }, \ 636 { "syn_cache_limit", CTLTYPE_INT }, \ 637 { "syn_bucket_limit", CTLTYPE_INT }, \ 638 { 0, 0 },\ 639 { "init_win", CTLTYPE_INT }, \ 640 { "mss_ifmtu", CTLTYPE_INT }, \ 641 { "sack", CTLTYPE_INT }, \ 642 { "win_scale", CTLTYPE_INT }, \ 643 { "timestamps", CTLTYPE_INT }, \ 644 { "compat_42", CTLTYPE_INT }, \ 645 { "cwm", CTLTYPE_INT }, \ 646 { "cwm_burstsize", CTLTYPE_INT }, \ 647 { "ack_on_push", CTLTYPE_INT }, \ 648 { "keepidle", CTLTYPE_INT }, \ 649 { "keepintvl", CTLTYPE_INT }, \ 650 { "keepcnt", CTLTYPE_INT }, \ 651 { "slowhz", CTLTYPE_INT }, \ 652 { "newreno", CTLTYPE_INT }, \ 653 { "log_refused",CTLTYPE_INT }, \ 654 { 0, 0 }, \ 655 { "rstppslimit", CTLTYPE_INT }, \ 656 { "delack_ticks", CTLTYPE_INT }, \ 657 { "init_win_local", CTLTYPE_INT }, \ 658 { "ident", CTLTYPE_STRUCT }, \ 659 { "ackdropppslimit", CTLTYPE_INT }, \ 660 { "do_loopback_cksum", CTLTYPE_INT }, \ 661 } 662 663 #ifdef _KERNEL 664 extern struct inpcbtable tcbtable; /* head of queue of active tcpcb's */ 665 extern struct tcpstat tcpstat; /* tcp statistics */ 666 extern u_int32_t tcp_now; /* for RFC 1323 timestamps */ 667 extern int tcp_do_rfc1323; /* enabled/disabled? */ 668 extern int tcp_do_sack; /* SACK enabled/disabled? */ 669 extern int tcp_do_win_scale; /* RFC1323 window scaling enabled/disabled? */ 670 extern int tcp_do_timestamps; /* RFC1323 timestamps enabled/disabled? */ 671 extern int tcp_do_newreno; /* Use the New Reno algorithms */ 672 extern int tcp_mssdflt; /* default seg size */ 673 extern int tcp_init_win; /* initial window */ 674 extern int tcp_init_win_local; /* initial window for local nets */ 675 extern int tcp_mss_ifmtu; /* take MSS from interface, not in_maxmtu */ 676 extern int tcp_compat_42; /* work around ancient broken TCP peers */ 677 extern int tcp_cwm; /* enable Congestion Window Monitoring */ 678 extern int tcp_cwm_burstsize; /* burst size allowed by CWM */ 679 extern int tcp_ack_on_push; /* ACK immediately on PUSH */ 680 extern int tcp_syn_cache_limit; /* max entries for compressed state engine */ 681 extern int tcp_syn_bucket_limit;/* max entries per hash bucket */ 682 extern int tcp_log_refused; /* log refused connections */ 683 extern int tcp_do_loopback_cksum;/* do TCP checksum on loopback? */ 684 685 extern int tcp_rst_ppslim; 686 extern int tcp_ackdrop_ppslim; 687 688 extern int tcp_syn_cache_size; 689 extern struct syn_cache_head tcp_syn_cache[]; 690 extern u_long syn_cache_count; 691 692 extern struct pool tcpipqent_pool; 693 694 #ifdef MBUFTRACE 695 extern struct mowner tcp_rx_mowner; 696 extern struct mowner tcp_tx_mowner; 697 extern struct mowner tcp_mowner; 698 #endif 699 700 #define TCPCTL_VARIABLES { \ 701 { 0 }, \ 702 { 1, 0, &tcp_do_rfc1323 }, \ 703 { 1, 0, &tcp_sendspace }, \ 704 { 1, 0, &tcp_recvspace }, \ 705 { 1, 0, &tcp_mssdflt }, \ 706 { 1, 0, &tcp_syn_cache_limit }, \ 707 { 1, 0, &tcp_syn_bucket_limit }, \ 708 { 0 }, \ 709 { 1, 0, &tcp_init_win }, \ 710 { 1, 0, &tcp_mss_ifmtu }, \ 711 { 1, 0, &tcp_do_sack }, \ 712 { 1, 0, &tcp_do_win_scale }, \ 713 { 1, 0, &tcp_do_timestamps }, \ 714 { 1, 0, &tcp_compat_42 }, \ 715 { 1, 0, &tcp_cwm }, \ 716 { 1, 0, &tcp_cwm_burstsize }, \ 717 { 1, 0, &tcp_ack_on_push }, \ 718 { 1, 0, &tcp_keepidle }, \ 719 { 1, 0, &tcp_keepintvl }, \ 720 { 1, 0, &tcp_keepcnt }, \ 721 { 1, 1, 0, PR_SLOWHZ }, \ 722 { 1, 0, &tcp_do_newreno }, \ 723 { 1, 0, &tcp_log_refused }, \ 724 { 0 }, \ 725 { 1, 0, &tcp_rst_ppslim }, \ 726 { 1, 0, &tcp_delack_ticks }, \ 727 { 1, 0, &tcp_init_win_local }, \ 728 { 1, 0, &tcp_ackdrop_ppslim }, \ 729 } 730 731 #ifdef __NO_STRICT_ALIGNMENT 732 #define TCP_HDR_ALIGNED_P(th) 1 733 #else 734 #define TCP_HDR_ALIGNED_P(th) ((((vaddr_t)(th)) & 3) == 0) 735 #endif 736 737 struct secasvar; 738 739 int tcp_attach(struct socket *); 740 void tcp_canceltimers(struct tcpcb *); 741 int tcp_timers_invoking(struct tcpcb*); 742 struct tcpcb * 743 tcp_close(struct tcpcb *); 744 int tcp_isdead(struct tcpcb *); 745 #ifdef INET6 746 void tcp6_ctlinput(int, struct sockaddr *, void *); 747 #endif 748 void *tcp_ctlinput(int, struct sockaddr *, void *); 749 int tcp_ctloutput(int, struct socket *, int, int, struct mbuf **); 750 struct tcpcb * 751 tcp_disconnect(struct tcpcb *); 752 struct tcpcb * 753 tcp_drop(struct tcpcb *, int); 754 #ifdef TCP_SIGNATURE 755 int tcp_signature_apply(void *, caddr_t, u_int); 756 struct secasvar *tcp_signature_getsav(struct mbuf *, struct tcphdr *); 757 int tcp_signature(struct mbuf *, struct tcphdr *, int, struct secasvar *, 758 char *); 759 #endif 760 int tcp_dooptions(struct tcpcb *, u_char *, int, struct tcphdr *, 761 struct mbuf *, int, struct tcp_opt_info *); 762 void tcp_drain(void); 763 void tcp_established(struct tcpcb *); 764 void tcp_init(void); 765 #ifdef INET6 766 int tcp6_input(struct mbuf **, int *, int); 767 #endif 768 void tcp_input(struct mbuf *, ...); 769 u_long tcp_mss_to_advertise(const struct ifnet *, int); 770 void tcp_mss_from_peer(struct tcpcb *, int); 771 void tcp_tcpcb_template(void); 772 struct tcpcb * 773 tcp_newtcpcb(int, void *); 774 void tcp_notify(struct inpcb *, int); 775 #ifdef INET6 776 void tcp6_notify(struct in6pcb *, int); 777 #endif 778 u_int tcp_optlen(struct tcpcb *); 779 int tcp_output(struct tcpcb *); 780 void tcp_pulloutofband(struct socket *, 781 struct tcphdr *, struct mbuf *, int); 782 void tcp_quench(struct inpcb *, int); 783 #ifdef INET6 784 void tcp6_quench(struct in6pcb *, int); 785 #endif 786 int tcp_reass(struct tcpcb *, struct tcphdr *, struct mbuf *, int *); 787 int tcp_respond(struct tcpcb *, struct mbuf *, struct mbuf *, 788 struct tcphdr *, tcp_seq, tcp_seq, int); 789 void tcp_rmx_rtt(struct tcpcb *); 790 void tcp_setpersist(struct tcpcb *); 791 #ifdef TCP_SIGNATURE 792 int tcp_signature_compute(struct mbuf *, struct tcphdr *, int, int, 793 int, u_char *, u_int); 794 #endif 795 void tcp_slowtimo(void); 796 struct mbuf * 797 tcp_template(struct tcpcb *); 798 void tcp_trace(short, short, struct tcpcb *, struct mbuf *, int); 799 struct tcpcb * 800 tcp_usrclosed(struct tcpcb *); 801 int tcp_sysctl(int *, u_int, void *, size_t *, void *, size_t); 802 int tcp_usrreq(struct socket *, 803 int, struct mbuf *, struct mbuf *, struct mbuf *, struct proc *); 804 void tcp_xmit_timer(struct tcpcb *, uint32_t); 805 tcp_seq tcp_new_iss(struct tcpcb *, tcp_seq); 806 tcp_seq tcp_new_iss1(void *, void *, u_int16_t, u_int16_t, size_t, 807 tcp_seq); 808 809 int syn_cache_add(struct sockaddr *, struct sockaddr *, 810 struct tcphdr *, unsigned int, struct socket *, 811 struct mbuf *, u_char *, int, struct tcp_opt_info *); 812 void syn_cache_unreach(struct sockaddr *, struct sockaddr *, 813 struct tcphdr *); 814 struct socket *syn_cache_get(struct sockaddr *, struct sockaddr *, 815 struct tcphdr *, unsigned int, unsigned int, 816 struct socket *so, struct mbuf *); 817 void syn_cache_init(void); 818 void syn_cache_insert(struct syn_cache *, struct tcpcb *); 819 struct syn_cache *syn_cache_lookup(struct sockaddr *, struct sockaddr *, 820 struct syn_cache_head **); 821 void syn_cache_reset(struct sockaddr *, struct sockaddr *, 822 struct tcphdr *); 823 int syn_cache_respond(struct syn_cache *, struct mbuf *); 824 void syn_cache_timer(void *); 825 void syn_cache_cleanup(struct tcpcb *); 826 827 void tcp_reno_newack(struct tcpcb *, struct tcphdr *); 828 void tcp_newreno_newack(struct tcpcb *, struct tcphdr *); 829 830 int tcp_input_checksum(int, struct mbuf *, const struct tcphdr *, int, int, 831 int); 832 #endif 833 834 #endif /* _NETINET_TCP_VAR_H_ */ 835