tcp_var.h revision 1.112 1 /* $NetBSD: tcp_var.h,v 1.112 2004/05/18 14:44:16 itojun 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 /* receive sequence variables */
221 u_long rcv_wnd; /* receive window */
222 tcp_seq rcv_nxt; /* receive next */
223 tcp_seq rcv_up; /* receive urgent pointer */
224 tcp_seq irs; /* initial receive sequence number */
225 /*
226 * Additional variables for this implementation.
227 */
228 /* receive variables */
229 tcp_seq rcv_adv; /* advertised window */
230 /* retransmit variables */
231 tcp_seq snd_max; /* highest sequence number sent;
232 * used to recognize retransmits
233 */
234 /* congestion control (for slow start, source quench, retransmit after loss) */
235 u_long snd_cwnd; /* congestion-controlled window */
236 u_long snd_ssthresh; /* snd_cwnd size threshhold for
237 * for slow start exponential to
238 * linear switch
239 */
240 /*
241 * transmit timing stuff. See below for scale of srtt and rttvar.
242 * "Variance" is actually smoothed difference.
243 */
244 uint32_t t_rcvtime; /* time last segment received */
245 uint32_t t_rtttime; /* time we started measuring rtt */
246 tcp_seq t_rtseq; /* sequence number being timed */
247 int32_t t_srtt; /* smoothed round-trip time */
248 int32_t t_rttvar; /* variance in round-trip time */
249 uint32_t t_rttmin; /* minimum rtt allowed */
250 u_long max_sndwnd; /* largest window peer has offered */
251
252 /* out-of-band data */
253 char t_oobflags; /* have some */
254 char t_iobc; /* input character */
255 #define TCPOOB_HAVEDATA 0x01
256 #define TCPOOB_HADDATA 0x02
257 short t_softerror; /* possible error not yet reported */
258
259 /* RFC 1323 variables */
260 u_char snd_scale; /* window scaling for send window */
261 u_char rcv_scale; /* window scaling for recv window */
262 u_char request_r_scale; /* pending window scaling */
263 u_char requested_s_scale;
264 u_int32_t ts_recent; /* timestamp echo data */
265 u_int32_t ts_recent_age; /* when last updated */
266 u_int32_t ts_timebase; /* our timebase */
267 tcp_seq last_ack_sent;
268
269 /* SACK stuff */
270 struct ipqehead timeq; /* time sequenced queue (for SACK) */
271
272 /* path MTU discovery blackhole detection */
273 int t_mtudisc; /* perform mtudisc for this tcb */
274
275 /* pointer for syn cache entries*/
276 LIST_HEAD(, syn_cache) t_sc; /* list of entries by this tcb */
277
278 /* prediction of next mbuf when using large window sizes */
279 struct mbuf *t_lastm; /* last mbuf that data was sent from */
280 int t_inoff; /* data offset in previous mbuf */
281 int t_lastoff; /* last data address in mbuf chain */
282 int t_lastlen; /* last length read from mbuf chain */
283 };
284
285 #ifdef _KERNEL
286 /*
287 * TCP reassembly queue locks.
288 */
289 static __inline int tcp_reass_lock_try (struct tcpcb *)
290 __attribute__((__unused__));
291 static __inline void tcp_reass_unlock (struct tcpcb *)
292 __attribute__((__unused__));
293
294 static __inline int
295 tcp_reass_lock_try(tp)
296 struct tcpcb *tp;
297 {
298 int s;
299
300 /*
301 * Use splvm() -- we're blocking things that would cause
302 * mbuf allocation.
303 */
304 s = splvm();
305 if (tp->t_flags & TF_REASSEMBLING) {
306 splx(s);
307 return (0);
308 }
309 tp->t_flags |= TF_REASSEMBLING;
310 splx(s);
311 return (1);
312 }
313
314 static __inline void
315 tcp_reass_unlock(tp)
316 struct tcpcb *tp;
317 {
318 int s;
319
320 s = splvm();
321 tp->t_flags &= ~TF_REASSEMBLING;
322 splx(s);
323 }
324
325 #ifdef DIAGNOSTIC
326 #define TCP_REASS_LOCK(tp) \
327 do { \
328 if (tcp_reass_lock_try(tp) == 0) { \
329 printf("%s:%d: tcpcb %p reass already locked\n", \
330 __FILE__, __LINE__, tp); \
331 panic("tcp_reass_lock"); \
332 } \
333 } while (/*CONSTCOND*/ 0)
334 #define TCP_REASS_LOCK_CHECK(tp) \
335 do { \
336 if (((tp)->t_flags & TF_REASSEMBLING) == 0) { \
337 printf("%s:%d: tcpcb %p reass lock not held\n", \
338 __FILE__, __LINE__, tp); \
339 panic("tcp reass lock check"); \
340 } \
341 } while (/*CONSTCOND*/ 0)
342 #else
343 #define TCP_REASS_LOCK(tp) (void) tcp_reass_lock_try((tp))
344 #define TCP_REASS_LOCK_CHECK(tp) /* nothing */
345 #endif
346
347 #define TCP_REASS_UNLOCK(tp) tcp_reass_unlock((tp))
348 #endif /* _KERNEL */
349
350 /*
351 * Queue for delayed ACK processing.
352 */
353 #ifdef _KERNEL
354 extern int tcp_delack_ticks;
355 void tcp_delack(void *);
356
357 #define TCP_RESTART_DELACK(tp) \
358 callout_reset(&(tp)->t_delack_ch, tcp_delack_ticks, \
359 tcp_delack, tp)
360
361 #define TCP_SET_DELACK(tp) \
362 do { \
363 if (((tp)->t_flags & TF_DELACK) == 0) { \
364 (tp)->t_flags |= TF_DELACK; \
365 TCP_RESTART_DELACK(tp); \
366 } \
367 } while (/*CONSTCOND*/0)
368
369 #define TCP_CLEAR_DELACK(tp) \
370 do { \
371 if ((tp)->t_flags & TF_DELACK) { \
372 (tp)->t_flags &= ~TF_DELACK; \
373 callout_stop(&(tp)->t_delack_ch); \
374 } \
375 } while (/*CONSTCOND*/0)
376 #endif /* _KERNEL */
377
378 /*
379 * Compute the current timestamp for a connection.
380 */
381 #define TCP_TIMESTAMP(tp) (tcp_now - (tp)->ts_timebase)
382
383 /*
384 * Handy way of passing around TCP option info.
385 */
386 struct tcp_opt_info {
387 int ts_present;
388 u_int32_t ts_val;
389 u_int32_t ts_ecr;
390 u_int16_t maxseg;
391 };
392
393 #define TOF_SIGNATURE 0x0040 /* signature option present */
394 #define TOF_SIGLEN 0x0080 /* sigature length valid (RFC2385) */
395
396 /*
397 * Data for the TCP compressed state engine.
398 */
399 union syn_cache_sa {
400 struct sockaddr sa;
401 struct sockaddr_in sin;
402 #if 1 /*def INET6*/
403 struct sockaddr_in6 sin6;
404 #endif
405 };
406
407 struct syn_cache {
408 TAILQ_ENTRY(syn_cache) sc_bucketq; /* link on bucket list */
409 struct callout sc_timer; /* rexmt timer */
410 union { /* cached route */
411 struct route route4;
412 #ifdef INET6
413 struct route_in6 route6;
414 #endif
415 } sc_route_u;
416 #define sc_route4 sc_route_u.route4
417 #ifdef INET6
418 #define sc_route6 sc_route_u.route6
419 #endif
420 long sc_win; /* advertised window */
421 int sc_bucketidx; /* our bucket index */
422 u_int32_t sc_hash;
423 u_int32_t sc_timestamp; /* timestamp from SYN */
424 u_int32_t sc_timebase; /* our local timebase */
425 union syn_cache_sa sc_src;
426 union syn_cache_sa sc_dst;
427 tcp_seq sc_irs;
428 tcp_seq sc_iss;
429 u_int sc_rxtcur; /* current rxt timeout */
430 u_int sc_rxttot; /* total time spend on queues */
431 u_short sc_rxtshift; /* for computing backoff */
432 u_short sc_flags;
433
434 #define SCF_UNREACH 0x0001 /* we've had an unreach error */
435 #define SCF_TIMESTAMP 0x0002 /* peer will do timestamps */
436 #define SCF_DEAD 0x0004 /* this entry to be released */
437 #define SCF_SIGNATURE 0x40 /* send MD5 digests */
438
439 struct mbuf *sc_ipopts; /* IP options */
440 u_int16_t sc_peermaxseg;
441 u_int16_t sc_ourmaxseg;
442 u_int8_t sc_request_r_scale : 4,
443 sc_requested_s_scale : 4;
444
445 struct tcpcb *sc_tp; /* tcb for listening socket */
446 LIST_ENTRY(syn_cache) sc_tpq; /* list of entries by same tp */
447 };
448
449 struct syn_cache_head {
450 TAILQ_HEAD(, syn_cache) sch_bucket; /* bucket entries */
451 u_short sch_length; /* # entries in bucket */
452 };
453
454 #define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb)
455 #ifdef INET6
456 #define in6totcpcb(ip) ((struct tcpcb *)(ip)->in6p_ppcb)
457 #endif
458 #ifndef INET6
459 #define sototcpcb(so) (intotcpcb(sotoinpcb(so)))
460 #else
461 #define sototcpcb(so) (((so)->so_proto->pr_domain->dom_family == AF_INET) \
462 ? intotcpcb(sotoinpcb(so)) \
463 : in6totcpcb(sotoin6pcb(so)))
464 #endif
465
466 /*
467 * The smoothed round-trip time and estimated variance
468 * are stored as fixed point numbers scaled by the values below.
469 * For convenience, these scales are also used in smoothing the average
470 * (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed).
471 * With these scales, srtt has 3 bits to the right of the binary point,
472 * and thus an "ALPHA" of 0.875. rttvar has 2 bits to the right of the
473 * binary point, and is smoothed with an ALPHA of 0.75.
474 */
475 #define TCP_RTT_SHIFT 3 /* shift for srtt; 3 bits frac. */
476 #define TCP_RTTVAR_SHIFT 2 /* multiplier for rttvar; 2 bits */
477
478 /*
479 * The initial retransmission should happen at rtt + 4 * rttvar.
480 * Because of the way we do the smoothing, srtt and rttvar
481 * will each average +1/2 tick of bias. When we compute
482 * the retransmit timer, we want 1/2 tick of rounding and
483 * 1 extra tick because of +-1/2 tick uncertainty in the
484 * firing of the timer. The bias will give us exactly the
485 * 1.5 tick we need. But, because the bias is
486 * statistical, we have to test that we don't drop below
487 * the minimum feasible timer (which is 2 ticks).
488 * This macro assumes that the value of 1<<TCP_RTTVAR_SHIFT
489 * is the same as the multiplier for rttvar.
490 */
491 #define TCP_REXMTVAL(tp) \
492 ((((tp)->t_srtt >> TCP_RTT_SHIFT) + (tp)->t_rttvar) >> 2)
493
494 /*
495 * Compute the initial window for slow start.
496 */
497 #define TCP_INITIAL_WINDOW(iw, segsz) \
498 (((iw) == 0) ? (min(4 * (segsz), max(2 * (segsz), 4380))) : \
499 ((segsz) * (iw)))
500
501 /*
502 * TCP statistics.
503 * Many of these should be kept per connection,
504 * but that's inconvenient at the moment.
505 */
506 struct tcpstat {
507 u_quad_t tcps_connattempt; /* connections initiated */
508 u_quad_t tcps_accepts; /* connections accepted */
509 u_quad_t tcps_connects; /* connections established */
510 u_quad_t tcps_drops; /* connections dropped */
511 u_quad_t tcps_conndrops; /* embryonic connections dropped */
512 u_quad_t tcps_closed; /* conn. closed (includes drops) */
513 u_quad_t tcps_segstimed; /* segs where we tried to get rtt */
514 u_quad_t tcps_rttupdated; /* times we succeeded */
515 u_quad_t tcps_delack; /* delayed acks sent */
516 u_quad_t tcps_timeoutdrop; /* conn. dropped in rxmt timeout */
517 u_quad_t tcps_rexmttimeo; /* retransmit timeouts */
518 u_quad_t tcps_persisttimeo; /* persist timeouts */
519 u_quad_t tcps_keeptimeo; /* keepalive timeouts */
520 u_quad_t tcps_keepprobe; /* keepalive probes sent */
521 u_quad_t tcps_keepdrops; /* connections dropped in keepalive */
522 u_quad_t tcps_persistdrops; /* connections dropped in persist */
523 u_quad_t tcps_connsdrained; /* connections drained due to memory
524 shortage */
525 u_quad_t tcps_pmtublackhole; /* PMTUD blackhole detected */
526
527 u_quad_t tcps_sndtotal; /* total packets sent */
528 u_quad_t tcps_sndpack; /* data packets sent */
529 u_quad_t tcps_sndbyte; /* data bytes sent */
530 u_quad_t tcps_sndrexmitpack; /* data packets retransmitted */
531 u_quad_t tcps_sndrexmitbyte; /* data bytes retransmitted */
532 u_quad_t tcps_sndacks; /* ack-only packets sent */
533 u_quad_t tcps_sndprobe; /* window probes sent */
534 u_quad_t tcps_sndurg; /* packets sent with URG only */
535 u_quad_t tcps_sndwinup; /* window update-only packets sent */
536 u_quad_t tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */
537
538 u_quad_t tcps_rcvtotal; /* total packets received */
539 u_quad_t tcps_rcvpack; /* packets received in sequence */
540 u_quad_t tcps_rcvbyte; /* bytes received in sequence */
541 u_quad_t tcps_rcvbadsum; /* packets received with ccksum errs */
542 u_quad_t tcps_rcvbadoff; /* packets received with bad offset */
543 u_quad_t tcps_rcvmemdrop; /* packets dropped for lack of memory */
544 u_quad_t tcps_rcvshort; /* packets received too short */
545 u_quad_t tcps_rcvduppack; /* duplicate-only packets received */
546 u_quad_t tcps_rcvdupbyte; /* duplicate-only bytes received */
547 u_quad_t tcps_rcvpartduppack; /* packets with some duplicate data */
548 u_quad_t tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */
549 u_quad_t tcps_rcvoopack; /* out-of-order packets received */
550 u_quad_t tcps_rcvoobyte; /* out-of-order bytes received */
551 u_quad_t tcps_rcvpackafterwin; /* packets with data after window */
552 u_quad_t tcps_rcvbyteafterwin; /* bytes rcvd after window */
553 u_quad_t tcps_rcvafterclose; /* packets rcvd after "close" */
554 u_quad_t tcps_rcvwinprobe; /* rcvd window probe packets */
555 u_quad_t tcps_rcvdupack; /* rcvd duplicate acks */
556 u_quad_t tcps_rcvacktoomuch; /* rcvd acks for unsent data */
557 u_quad_t tcps_rcvackpack; /* rcvd ack packets */
558 u_quad_t tcps_rcvackbyte; /* bytes acked by rcvd acks */
559 u_quad_t tcps_rcvwinupd; /* rcvd window update packets */
560 u_quad_t tcps_pawsdrop; /* segments dropped due to PAWS */
561 u_quad_t tcps_predack; /* times hdr predict ok for acks */
562 u_quad_t tcps_preddat; /* times hdr predict ok for data pkts */
563
564 u_quad_t tcps_pcbhashmiss; /* input packets missing pcb hash */
565 u_quad_t tcps_noport; /* no socket on port */
566 u_quad_t tcps_badsyn; /* received ack for which we have
567 no SYN in compressed state */
568 u_quad_t tcps_delayed_free; /* delayed pool_put() of tcpcb */
569
570 /* These statistics deal with the SYN cache. */
571 u_quad_t tcps_sc_added; /* # of entries added */
572 u_quad_t tcps_sc_completed; /* # of connections completed */
573 u_quad_t tcps_sc_timed_out; /* # of entries timed out */
574 u_quad_t tcps_sc_overflowed; /* # dropped due to overflow */
575 u_quad_t tcps_sc_reset; /* # dropped due to RST */
576 u_quad_t tcps_sc_unreach; /* # dropped due to ICMP unreach */
577 u_quad_t tcps_sc_bucketoverflow;/* # dropped due to bucket overflow */
578 u_quad_t tcps_sc_aborted; /* # of entries aborted (no mem) */
579 u_quad_t tcps_sc_dupesyn; /* # of duplicate SYNs received */
580 u_quad_t tcps_sc_dropped; /* # of SYNs dropped (no route/mem) */
581 u_quad_t tcps_sc_collisions; /* # of hash collisions */
582 u_quad_t tcps_sc_retransmitted; /* # of retransmissions */
583 u_quad_t tcps_sc_delayed_free; /* # of delayed pool_put()s */
584
585 u_quad_t tcps_selfquench; /* # of ENOBUFS we get on output */
586 u_quad_t tcps_badsig; /* # of drops due to bad signature */
587 u_quad_t tcps_goodsig; /* # of packets with good signature */
588 };
589
590 /*
591 * Names for TCP sysctl objects.
592 */
593 #define TCPCTL_RFC1323 1 /* RFC1323 timestamps/scaling */
594 #define TCPCTL_SENDSPACE 2 /* default send buffer */
595 #define TCPCTL_RECVSPACE 3 /* default recv buffer */
596 #define TCPCTL_MSSDFLT 4 /* default seg size */
597 #define TCPCTL_SYN_CACHE_LIMIT 5 /* max size of comp. state engine */
598 #define TCPCTL_SYN_BUCKET_LIMIT 6 /* max size of hash bucket */
599 #if 0 /*obsoleted*/
600 #define TCPCTL_SYN_CACHE_INTER 7 /* interval of comp. state timer */
601 #endif
602 #define TCPCTL_INIT_WIN 8 /* initial window */
603 #define TCPCTL_MSS_IFMTU 9 /* mss from interface, not in_maxmtu */
604 #define TCPCTL_SACK 10 /* RFC2018 selective acknowledgement */
605 #define TCPCTL_WSCALE 11 /* RFC1323 window scaling */
606 #define TCPCTL_TSTAMP 12 /* RFC1323 timestamps */
607 #define TCPCTL_COMPAT_42 13 /* 4.2BSD TCP bug work-arounds */
608 #define TCPCTL_CWM 14 /* Congestion Window Monitoring */
609 #define TCPCTL_CWM_BURSTSIZE 15 /* burst size allowed by CWM */
610 #define TCPCTL_ACK_ON_PUSH 16 /* ACK immediately on PUSH */
611 #define TCPCTL_KEEPIDLE 17 /* keepalive idle time */
612 #define TCPCTL_KEEPINTVL 18 /* keepalive probe interval */
613 #define TCPCTL_KEEPCNT 19 /* keepalive count */
614 #define TCPCTL_SLOWHZ 20 /* PR_SLOWHZ (read-only) */
615 #define TCPCTL_NEWRENO 21 /* NewReno Congestion Control */
616 #define TCPCTL_LOG_REFUSED 22 /* Log refused connections */
617 #if 0 /*obsoleted*/
618 #define TCPCTL_RSTRATELIMIT 23 /* RST rate limit */
619 #endif
620 #define TCPCTL_RSTPPSLIMIT 24 /* RST pps limit */
621 #define TCPCTL_DELACK_TICKS 25 /* # ticks to delay ACK */
622 #define TCPCTL_INIT_WIN_LOCAL 26 /* initial window for local nets */
623 #define TCPCTL_IDENT 27 /* rfc 931 identd */
624 #define TCPCTL_ACKDROPRATELIMIT 28 /* SYN/RST -> ACK rate limit */
625 #define TCPCTL_MAXID 29
626
627 #define TCPCTL_NAMES { \
628 { 0, 0 }, \
629 { "rfc1323", CTLTYPE_INT }, \
630 { "sendspace", CTLTYPE_INT }, \
631 { "recvspace", CTLTYPE_INT }, \
632 { "mssdflt", CTLTYPE_INT }, \
633 { "syn_cache_limit", CTLTYPE_INT }, \
634 { "syn_bucket_limit", CTLTYPE_INT }, \
635 { 0, 0 },\
636 { "init_win", CTLTYPE_INT }, \
637 { "mss_ifmtu", CTLTYPE_INT }, \
638 { "sack", CTLTYPE_INT }, \
639 { "win_scale", CTLTYPE_INT }, \
640 { "timestamps", CTLTYPE_INT }, \
641 { "compat_42", CTLTYPE_INT }, \
642 { "cwm", CTLTYPE_INT }, \
643 { "cwm_burstsize", CTLTYPE_INT }, \
644 { "ack_on_push", CTLTYPE_INT }, \
645 { "keepidle", CTLTYPE_INT }, \
646 { "keepintvl", CTLTYPE_INT }, \
647 { "keepcnt", CTLTYPE_INT }, \
648 { "slowhz", CTLTYPE_INT }, \
649 { "newreno", CTLTYPE_INT }, \
650 { "log_refused",CTLTYPE_INT }, \
651 { 0, 0 }, \
652 { "rstppslimit", CTLTYPE_INT }, \
653 { "delack_ticks", CTLTYPE_INT }, \
654 { "init_win_local", CTLTYPE_INT }, \
655 { "ident", CTLTYPE_STRUCT }, \
656 { "ackdropppslimit", CTLTYPE_INT }, \
657 }
658
659 #ifdef _KERNEL
660 extern struct inpcbtable tcbtable; /* head of queue of active tcpcb's */
661 extern struct tcpstat tcpstat; /* tcp statistics */
662 extern u_int32_t tcp_now; /* for RFC 1323 timestamps */
663 extern int tcp_do_rfc1323; /* enabled/disabled? */
664 extern int tcp_do_sack; /* SACK enabled/disabled? */
665 extern int tcp_do_win_scale; /* RFC1323 window scaling enabled/disabled? */
666 extern int tcp_do_timestamps; /* RFC1323 timestamps enabled/disabled? */
667 extern int tcp_do_newreno; /* Use the New Reno algorithms */
668 extern int tcp_mssdflt; /* default seg size */
669 extern int tcp_init_win; /* initial window */
670 extern int tcp_init_win_local; /* initial window for local nets */
671 extern int tcp_mss_ifmtu; /* take MSS from interface, not in_maxmtu */
672 extern int tcp_compat_42; /* work around ancient broken TCP peers */
673 extern int tcp_cwm; /* enable Congestion Window Monitoring */
674 extern int tcp_cwm_burstsize; /* burst size allowed by CWM */
675 extern int tcp_ack_on_push; /* ACK immediately on PUSH */
676 extern int tcp_syn_cache_limit; /* max entries for compressed state engine */
677 extern int tcp_syn_bucket_limit;/* max entries per hash bucket */
678 extern int tcp_log_refused; /* log refused connections */
679
680 extern int tcp_rst_ppslim;
681 extern int tcp_ackdrop_ppslim;
682
683 extern int tcp_syn_cache_size;
684 extern struct syn_cache_head tcp_syn_cache[];
685 extern u_long syn_cache_count;
686
687 #ifdef MBUFTRACE
688 extern struct mowner tcp_rx_mowner;
689 extern struct mowner tcp_tx_mowner;
690 extern struct mowner tcp_mowner;
691 #endif
692
693 #define TCPCTL_VARIABLES { \
694 { 0 }, \
695 { 1, 0, &tcp_do_rfc1323 }, \
696 { 1, 0, &tcp_sendspace }, \
697 { 1, 0, &tcp_recvspace }, \
698 { 1, 0, &tcp_mssdflt }, \
699 { 1, 0, &tcp_syn_cache_limit }, \
700 { 1, 0, &tcp_syn_bucket_limit }, \
701 { 0 }, \
702 { 1, 0, &tcp_init_win }, \
703 { 1, 0, &tcp_mss_ifmtu }, \
704 { 1, 0, &tcp_do_sack }, \
705 { 1, 0, &tcp_do_win_scale }, \
706 { 1, 0, &tcp_do_timestamps }, \
707 { 1, 0, &tcp_compat_42 }, \
708 { 1, 0, &tcp_cwm }, \
709 { 1, 0, &tcp_cwm_burstsize }, \
710 { 1, 0, &tcp_ack_on_push }, \
711 { 1, 0, &tcp_keepidle }, \
712 { 1, 0, &tcp_keepintvl }, \
713 { 1, 0, &tcp_keepcnt }, \
714 { 1, 1, 0, PR_SLOWHZ }, \
715 { 1, 0, &tcp_do_newreno }, \
716 { 1, 0, &tcp_log_refused }, \
717 { 0 }, \
718 { 1, 0, &tcp_rst_ppslim }, \
719 { 1, 0, &tcp_delack_ticks }, \
720 { 1, 0, &tcp_init_win_local }, \
721 { 1, 0, &tcp_ackdrop_ppslim }, \
722 }
723
724 #ifdef __NO_STRICT_ALIGNMENT
725 #define TCP_HDR_ALIGNED_P(th) 1
726 #else
727 #define TCP_HDR_ALIGNED_P(th) ((((vaddr_t)(th)) & 3) == 0)
728 #endif
729
730 struct secasvar;
731
732 int tcp_attach(struct socket *);
733 void tcp_canceltimers(struct tcpcb *);
734 int tcp_timers_invoking(struct tcpcb*);
735 struct tcpcb *
736 tcp_close(struct tcpcb *);
737 int tcp_isdead(struct tcpcb *);
738 #ifdef INET6
739 void tcp6_ctlinput(int, struct sockaddr *, void *);
740 #endif
741 void *tcp_ctlinput(int, struct sockaddr *, void *);
742 int tcp_ctloutput(int, struct socket *, int, int, struct mbuf **);
743 struct tcpcb *
744 tcp_disconnect(struct tcpcb *);
745 struct tcpcb *
746 tcp_drop(struct tcpcb *, int);
747 #ifdef TCP_SIGNATURE
748 int tcp_signature_apply(void *, caddr_t, u_int);
749 struct secasvar *tcp_signature_getsav(struct mbuf *, struct tcphdr *);
750 int tcp_signature(struct mbuf *, struct tcphdr *, int, struct secasvar *,
751 char *);
752 #endif
753 int tcp_dooptions(struct tcpcb *, u_char *, int, struct tcphdr *,
754 struct mbuf *, int, struct tcp_opt_info *);
755 void tcp_drain(void);
756 void tcp_established(struct tcpcb *);
757 void tcp_init(void);
758 #ifdef INET6
759 int tcp6_input(struct mbuf **, int *, int);
760 #endif
761 void tcp_input(struct mbuf *, ...);
762 u_long tcp_mss_to_advertise(const struct ifnet *, int);
763 void tcp_mss_from_peer(struct tcpcb *, int);
764 void tcp_tcpcb_template(void);
765 struct tcpcb *
766 tcp_newtcpcb(int, void *);
767 void tcp_notify(struct inpcb *, int);
768 #ifdef INET6
769 void tcp6_notify(struct in6pcb *, int);
770 #endif
771 u_int tcp_optlen(struct tcpcb *);
772 int tcp_output(struct tcpcb *);
773 void tcp_pulloutofband(struct socket *,
774 struct tcphdr *, struct mbuf *, int);
775 void tcp_quench(struct inpcb *, int);
776 #ifdef INET6
777 void tcp6_quench(struct in6pcb *, int);
778 #endif
779 int tcp_reass(struct tcpcb *, struct tcphdr *, struct mbuf *, int *);
780 int tcp_respond(struct tcpcb *, struct mbuf *, struct mbuf *,
781 struct tcphdr *, tcp_seq, tcp_seq, int);
782 void tcp_rmx_rtt(struct tcpcb *);
783 void tcp_setpersist(struct tcpcb *);
784 #ifdef TCP_SIGNATURE
785 int tcp_signature_compute(struct mbuf *, struct tcphdr *, int, int,
786 int, u_char *, u_int);
787 #endif
788 void tcp_slowtimo(void);
789 struct mbuf *
790 tcp_template(struct tcpcb *);
791 void tcp_trace(int, int, struct tcpcb *, struct mbuf *, int);
792 struct tcpcb *
793 tcp_usrclosed(struct tcpcb *);
794 int tcp_sysctl(int *, u_int, void *, size_t *, void *, size_t);
795 int tcp_usrreq(struct socket *,
796 int, struct mbuf *, struct mbuf *, struct mbuf *, struct proc *);
797 void tcp_xmit_timer(struct tcpcb *, uint32_t);
798 tcp_seq tcp_new_iss(struct tcpcb *, tcp_seq);
799 tcp_seq tcp_new_iss1(void *, void *, u_int16_t, u_int16_t, size_t,
800 tcp_seq);
801
802 int syn_cache_add(struct sockaddr *, struct sockaddr *,
803 struct tcphdr *, unsigned int, struct socket *,
804 struct mbuf *, u_char *, int, struct tcp_opt_info *);
805 void syn_cache_unreach(struct sockaddr *, struct sockaddr *,
806 struct tcphdr *);
807 struct socket *syn_cache_get(struct sockaddr *, struct sockaddr *,
808 struct tcphdr *, unsigned int, unsigned int,
809 struct socket *so, struct mbuf *);
810 void syn_cache_init(void);
811 void syn_cache_insert(struct syn_cache *, struct tcpcb *);
812 struct syn_cache *syn_cache_lookup(struct sockaddr *, struct sockaddr *,
813 struct syn_cache_head **);
814 void syn_cache_reset(struct sockaddr *, struct sockaddr *,
815 struct tcphdr *);
816 int syn_cache_respond(struct syn_cache *, struct mbuf *);
817 void syn_cache_timer(void *);
818 void syn_cache_cleanup(struct tcpcb *);
819
820 int tcp_newreno(struct tcpcb *, struct tcphdr *);
821 #endif
822
823 #endif /* _NETINET_TCP_VAR_H_ */
824