summaryrefslogtreecommitdiff
path: root/sys/netinet/tcp_var.h
blob: 2b2184a046dda70567c86d3ae70d703c6fbddb50 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
/*	$OpenBSD: tcp_var.h,v 1.122 2017/02/09 15:19:32 jca Exp $	*/
/*	$NetBSD: tcp_var.h,v 1.17 1996/02/13 23:44:24 christos Exp $	*/

/*
 * Copyright (c) 1982, 1986, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)tcp_var.h	8.3 (Berkeley) 4/10/94
 */

#ifndef _NETINET_TCP_VAR_H_
#define _NETINET_TCP_VAR_H_

#include <sys/timeout.h>

/*
 * Kernel variables for tcp.
 */

struct sackblk {
	tcp_seq start;		/* start seq no. of sack block */
	tcp_seq end; 		/* end seq no. */
};

struct sackhole {
	tcp_seq start;		/* start seq no. of hole */
	tcp_seq end;		/* end seq no. */
	int	dups;		/* number of dup(s)acks for this hole */
	tcp_seq rxmit;		/* next seq. no in hole to be retransmitted */
	struct sackhole *next;	/* next in list */
};

/*
 * TCP sequence queue structures.
 */
TAILQ_HEAD(tcpqehead, tcpqent);
struct tcpqent {
	TAILQ_ENTRY(tcpqent) tcpqe_q;
	struct tcphdr	*tcpqe_tcp;
	struct mbuf	*tcpqe_m;	/* mbuf contains packet */
};

/*
 * Tcp control block, one per tcp; fields:
 */
struct tcpcb {
	struct tcpqehead t_segq;		/* sequencing queue */
	struct timeout t_timer[TCPT_NTIMERS];	/* tcp timers */
	short	t_state;		/* state of this connection */
	short	t_rxtshift;		/* log(2) of rexmt exp. backoff */
	short	t_rxtcur;		/* current retransmit value */
	short	t_dupacks;		/* consecutive dup acks recd */
	u_short	t_maxseg;		/* maximum segment size */
	char	t_force;		/* 1 if forcing out a byte */
	u_int	t_flags;
#define	TF_ACKNOW	0x0001		/* ack peer immediately */
#define	TF_DELACK	0x0002		/* ack, but try to delay it */
#define	TF_NODELAY	0x0004		/* don't delay packets to coalesce */
#define	TF_NOOPT	0x0008		/* don't use tcp options */
#define	TF_SENTFIN	0x0010		/* have sent FIN */
#define	TF_REQ_SCALE	0x0020		/* have/will request window scaling */
#define	TF_RCVD_SCALE	0x0040		/* other side has requested scaling */
#define	TF_REQ_TSTMP	0x0080		/* have/will request timestamps */
#define	TF_RCVD_TSTMP	0x0100		/* a timestamp was received in SYN */
#define	TF_SACK_PERMIT	0x0200		/* other side said I could SACK */
#define	TF_SIGNATURE	0x0400		/* require TCP MD5 signature */
#ifdef TCP_ECN
#define TF_ECN_PERMIT	0x00008000	/* other side said I could ECN */
#define TF_RCVD_CE	0x00010000	/* send ECE in subsequent segs */
#define TF_SEND_CWR	0x00020000	/* send CWR in next seg */
#define TF_DISABLE_ECN	0x00040000	/* disable ECN for this connection */
#endif
#define TF_LASTIDLE	0x00100000	/* no outstanding ACK on last send */
#define TF_DEAD		0x00200000	/* dead and to-be-released */
#define TF_PMTUD_PEND	0x00400000	/* Path MTU Discovery pending */
#define TF_NEEDOUTPUT	0x00800000	/* call tcp_output after tcp_input */
#define TF_BLOCKOUTPUT	0x01000000	/* avert tcp_output during tcp_input */
#define TF_NOPUSH	0x02000000	/* don't push */

	struct	mbuf *t_template;	/* skeletal packet for transmit */
	struct	inpcb *t_inpcb;		/* back pointer to internet pcb */
	struct	timeout t_delack_to;	/* delayed ACK callback */
/*
 * The following fields are used as in the protocol specification.
 * See RFC793, Dec. 1981, page 21.
 */
/* send sequence variables */
	tcp_seq	snd_una;		/* send unacknowledged */
	tcp_seq	snd_nxt;		/* send next */
	tcp_seq	snd_up;			/* send urgent pointer */
	tcp_seq	snd_wl1;		/* window update seg seq number */
	tcp_seq	snd_wl2;		/* window update seg ack number */
	tcp_seq	iss;			/* initial send sequence number */
	u_long	snd_wnd;		/* send window */
#if 1 /*def TCP_SACK*/
	int	sack_enable;		/* enable SACK for this connection */
	int	snd_numholes;		/* number of holes seen by sender */
	struct sackhole *snd_holes;	/* linked list of holes (sorted) */
#if 1 /*defined(TCP_SACK) && defined(TCP_FACK)*/
	tcp_seq snd_fack;		/* for FACK congestion control */
	u_long	snd_awnd;		/* snd_nxt - snd_fack + */
					/* retransmitted data */
	int retran_data;		/* amount of outstanding retx. data  */
#endif /* TCP_FACK */
#endif /* TCP_SACK */
#if 1 /*defined(TCP_SACK) || defined(TCP_ECN)*/
	tcp_seq snd_last;		/* for use in fast recovery */
#endif
/* receive sequence variables */
	u_long	rcv_wnd;		/* receive window */
	tcp_seq	rcv_nxt;		/* receive next */
	tcp_seq	rcv_up;			/* receive urgent pointer */
	tcp_seq	irs;			/* initial receive sequence number */
#if 1 /*def TCP_SACK*/
	tcp_seq rcv_lastsack;		/* last seq number(+1) sack'd by rcv'r*/
	int	rcv_numsacks;		/* # distinct sack blks present */
	struct sackblk sackblks[MAX_SACK_BLKS]; /* seq nos. of sack blocks */
#endif

/*
 * Additional variables for this implementation.
 */
/* receive variables */
	tcp_seq	rcv_adv;		/* advertised window */
/* retransmit variables */
	tcp_seq	snd_max;		/* highest sequence number sent;
					 * used to recognize retransmits
					 */
/* congestion control (for slow start, source quench, retransmit after loss) */
	u_long	snd_cwnd;		/* congestion-controlled window */
	u_long	snd_ssthresh;		/* snd_cwnd size threshold for
					 * for slow start exponential to
					 * linear switch
					 */

/* auto-sizing variables */
	u_int	rfbuf_cnt;	/* recv buffer autoscaling byte count */
	u_int32_t rfbuf_ts;	/* recv buffer autoscaling time stamp */

	u_short	t_maxopd;		/* mss plus options */
	u_short	t_peermss;		/* peer's maximum segment size */

/*
 * transmit timing stuff.  See below for scale of srtt and rttvar.
 * "Variance" is actually smoothed difference.
 */
	uint32_t t_rcvtime;		/* time last segment received */
	uint32_t t_rtttime;		/* time we started measuring rtt */
	tcp_seq	t_rtseq;		/* sequence number being timed */
	short	t_srtt;			/* smoothed round-trip time */
	short	t_rttvar;		/* variance in round-trip time */
	u_short	t_rttmin;		/* minimum rtt allowed */
	u_long	max_sndwnd;		/* largest window peer has offered */

/* out-of-band data */
	char	t_oobflags;		/* have some */
	char	t_iobc;			/* input character */
#define	TCPOOB_HAVEDATA	0x01
#define	TCPOOB_HADDATA	0x02
	short	t_softerror;		/* possible error not yet reported */

/* RFC 1323 variables */
	u_char	snd_scale;		/* window scaling for send window */
	u_char	rcv_scale;		/* window scaling for recv window */
	u_char	request_r_scale;	/* pending window scaling */
	u_char	requested_s_scale;
	u_int32_t ts_recent;		/* timestamp echo data */
	u_int32_t ts_modulate;		/* modulation on timestamp */
	u_int32_t ts_recent_age;		/* when last updated */
	tcp_seq	last_ack_sent;

/* pointer for syn cache entries*/
	LIST_HEAD(, syn_cache) t_sc;	/* list of entries by this tcb */

/* Path-MTU Discovery Information */
	u_int	t_pmtud_mss_acked;	/* MSS acked, lower bound for MTU */
	u_int	t_pmtud_mtu_sent;	/* MTU used, upper bound for MTU */
	tcp_seq	t_pmtud_th_seq;		/* TCP SEQ from ICMP payload */
	u_int	t_pmtud_nextmtu;	/* Advertised Next-Hop MTU from ICMP */
	u_short	t_pmtud_ip_len;		/* IP length from ICMP payload */
	u_short	t_pmtud_ip_hl;		/* IP header length from ICMP payload */

	int pf;

	struct	timeout t_reap_to;	/* delayed cleanup timeout */
};

#define	intotcpcb(ip)	((struct tcpcb *)(ip)->inp_ppcb)
#define	sototcpcb(so)	(intotcpcb(sotoinpcb(so)))

#ifdef _KERNEL
extern int tcp_delack_ticks;
void	tcp_delack(void *);

#define TCP_INIT_DELACK(tp)						\
	timeout_set_proc(&(tp)->t_delack_to, tcp_delack, tp)

#define TCP_RESTART_DELACK(tp)						\
	timeout_add(&(tp)->t_delack_to, tcp_delack_ticks)

#define	TCP_SET_DELACK(tp)						\
do {									\
	if (((tp)->t_flags & TF_DELACK) == 0) {				\
		(tp)->t_flags |= TF_DELACK;				\
		TCP_RESTART_DELACK(tp);					\
	}								\
} while (/* CONSTCOND */ 0)

#define	TCP_CLEAR_DELACK(tp)						\
do {									\
	if ((tp)->t_flags & TF_DELACK) {				\
		(tp)->t_flags &= ~TF_DELACK;				\
		timeout_del(&(tp)->t_delack_to);			\
	}								\
} while (/* CONSTCOND */ 0)

/*
 * Handy way of passing around TCP option info.
 */
struct tcp_opt_info {
	int		ts_present;
	u_int32_t	ts_val;
	u_int32_t	ts_ecr;
	u_int16_t	maxseg;
};

/*
 * Data for the TCP compressed state engine.
 */

#define	TCP_SYN_HASH_SIZE	293
#define	TCP_SYN_BUCKET_SIZE	35

union syn_cache_sa {
	struct sockaddr sa;
	struct sockaddr_in sin;
	struct sockaddr_in6 sin6;
};

struct syn_cache {
	TAILQ_ENTRY(syn_cache) sc_bucketq;	/* link on bucket list */
	struct timeout sc_timer;		/* rexmt timer */
	union {					/* cached route */
		struct route route4;
#ifdef INET6
		struct route_in6 route6;
#endif
	} sc_route_u;
#define sc_route4	sc_route_u.route4
#ifdef INET6
#define sc_route6	sc_route_u.route6
#endif
	long sc_win;				/* advertised window */
	struct syn_cache_head *sc_buckethead;	/* our bucket index */
	struct syn_cache_set *sc_set;		/* our syn cache set */
	u_int32_t sc_hash;
	u_int32_t sc_timestamp;			/* timestamp from SYN */
	u_int32_t sc_modulate;			/* our timestamp modulator */
#if 0
	u_int32_t sc_timebase;			/* our local timebase */
#endif
	union syn_cache_sa sc_src;
	union syn_cache_sa sc_dst;
	tcp_seq sc_irs;
	tcp_seq sc_iss;
	u_int sc_rtableid;
	u_int sc_rxtcur;			/* current rxt timeout */
	u_int sc_rxttot;			/* total time spend on queues */
	u_short sc_rxtshift;			/* for computing backoff */
	u_short sc_flags;

#define	SCF_UNREACH		0x0001		/* we've had an unreach error */
#define	SCF_TIMESTAMP		0x0002		/* peer will do timestamps */
#define	SCF_DEAD		0x0004		/* this entry to be released */
#define	SCF_SACK_PERMIT		0x0008		/* permit sack */
#define	SCF_ECN_PERMIT		0x0010		/* permit ecn */
#define	SCF_SIGNATURE		0x0020		/* enforce tcp signatures */

	struct mbuf *sc_ipopts;			/* IP options */
	u_int16_t sc_peermaxseg;
	u_int16_t sc_ourmaxseg;
	u_int     sc_request_r_scale	: 4,
		  sc_requested_s_scale	: 4;

	struct tcpcb *sc_tp;			/* tcb for listening socket */
	LIST_ENTRY(syn_cache) sc_tpq;		/* list of entries by same tp */
};

struct syn_cache_head {
	TAILQ_HEAD(, syn_cache) sch_bucket;	/* bucket entries */
	u_short sch_length;			/* # entries in bucket */
};

struct syn_cache_set {
	struct		syn_cache_head *scs_buckethead;
	int		scs_size;
	int		scs_count;
	int		scs_use;
	u_int32_t	scs_random[5];
};

#endif /* _KERNEL */

/*
 * The smoothed round-trip time and estimated variance
 * are stored as fixed point numbers scaled by the values below.
 * For convenience, these scales are also used in smoothing the average
 * (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed).
 * With these scales, srtt has 5 bits to the right of the binary point,
 * and thus an "ALPHA" of 0.875.  rttvar has 4 bits to the right of the
 * binary point, and is smoothed with an ALPHA of 0.75.
 */
#define	TCP_RTT_SHIFT		3	/* shift for srtt; 5 bits frac. */
#define	TCP_RTTVAR_SHIFT	2	/* shift for rttvar; 4 bits */
#define	TCP_RTT_BASE_SHIFT	2	/* remaining 2 bit shift */
#define	TCP_RTT_MAX		(1<<9)	/* maximum rtt */

/*
 * The initial retransmission should happen at rtt + 4 * rttvar.
 * Because of the way we do the smoothing, srtt and rttvar
 * will each average +1/2 tick of bias.  When we compute
 * the retransmit timer, we want 1/2 tick of rounding and
 * 1 extra tick because of +-1/2 tick uncertainty in the
 * firing of the timer.  The bias will give us exactly the
 * 1.5 tick we need.  But, because the bias is
 * statistical, we have to test that we don't drop below
 * the minimum feasible timer (which is 2 ticks).
 * This macro assumes that the value of (1 << TCP_RTTVAR_SHIFT)
 * is the same as the multiplier for rttvar.
 */
#define	TCP_REXMTVAL(tp) \
	((((tp)->t_srtt >> TCP_RTT_SHIFT) + (tp)->t_rttvar) >> TCP_RTT_BASE_SHIFT)

/*
 * TCP statistics.
 * Many of these should be kept per connection,
 * but that's inconvenient at the moment.
 */
struct	tcpstat {
	u_int32_t tcps_connattempt;	/* connections initiated */
	u_int32_t tcps_accepts;		/* connections accepted */
	u_int32_t tcps_connects;	/* connections established */
	u_int32_t tcps_drops;		/* connections dropped */
	u_int32_t tcps_conndrops;	/* embryonic connections dropped */
	u_int32_t tcps_closed;		/* conn. closed (includes drops) */
	u_int32_t tcps_segstimed;	/* segs where we tried to get rtt */
	u_int32_t tcps_rttupdated;	/* times we succeeded */
	u_int32_t tcps_delack;		/* delayed acks sent */
	u_int32_t tcps_timeoutdrop;	/* conn. dropped in rxmt timeout */
	u_int32_t tcps_rexmttimeo;	/* retransmit timeouts */
	u_int32_t tcps_persisttimeo;	/* persist timeouts */
	u_int32_t tcps_persistdrop;	/* connections dropped in persist */
	u_int32_t tcps_keeptimeo;	/* keepalive timeouts */
	u_int32_t tcps_keepprobe;	/* keepalive probes sent */
	u_int32_t tcps_keepdrops;	/* connections dropped in keepalive */

	u_int32_t tcps_sndtotal;		/* total packets sent */
	u_int32_t tcps_sndpack;		/* data packets sent */
	u_int64_t tcps_sndbyte;		/* data bytes sent */
	u_int32_t tcps_sndrexmitpack;	/* data packets retransmitted */
	u_int64_t tcps_sndrexmitbyte;	/* data bytes retransmitted */
	u_int64_t tcps_sndrexmitfast;	/* Fast retransmits */
	u_int32_t tcps_sndacks;		/* ack-only packets sent */
	u_int32_t tcps_sndprobe;	/* window probes sent */
	u_int32_t tcps_sndurg;		/* packets sent with URG only */
	u_int32_t tcps_sndwinup;	/* window update-only packets sent */
	u_int32_t tcps_sndctrl;		/* control (SYN|FIN|RST) packets sent */

	u_int32_t tcps_rcvtotal;	/* total packets received */
	u_int32_t tcps_rcvpack;		/* packets received in sequence */
	u_int64_t tcps_rcvbyte;		/* bytes received in sequence */
	u_int32_t tcps_rcvbadsum;	/* packets received with ccksum errs */
	u_int32_t tcps_rcvbadoff;	/* packets received with bad offset */
	u_int32_t tcps_rcvmemdrop;	/* packets dropped for lack of memory */
	u_int32_t tcps_rcvnosec;	/* packets dropped for lack of ipsec */
	u_int32_t tcps_rcvshort;	/* packets received too short */
	u_int32_t tcps_rcvduppack;	/* duplicate-only packets received */
	u_int64_t tcps_rcvdupbyte;	/* duplicate-only bytes received */
	u_int32_t tcps_rcvpartduppack;	/* packets with some duplicate data */
	u_int64_t tcps_rcvpartdupbyte;	/* dup. bytes in part-dup. packets */
	u_int32_t tcps_rcvoopack;	/* out-of-order packets received */
	u_int64_t tcps_rcvoobyte;	/* out-of-order bytes received */
	u_int32_t tcps_rcvpackafterwin;	/* packets with data after window */
	u_int64_t tcps_rcvbyteafterwin;	/* bytes rcvd after window */
	u_int32_t tcps_rcvafterclose;	/* packets rcvd after "close" */
	u_int32_t tcps_rcvwinprobe;	/* rcvd window probe packets */
	u_int32_t tcps_rcvdupack;	/* rcvd duplicate acks */
	u_int32_t tcps_rcvacktoomuch;	/* rcvd acks for unsent data */
	u_int32_t tcps_rcvacktooold;	/* rcvd acks for old data */
	u_int32_t tcps_rcvackpack;	/* rcvd ack packets */
	u_int64_t tcps_rcvackbyte;	/* bytes acked by rcvd acks */
	u_int32_t tcps_rcvwinupd;	/* rcvd window update packets */
	u_int32_t tcps_pawsdrop;	/* segments dropped due to PAWS */
	u_int32_t tcps_predack;		/* times hdr predict ok for acks */
	u_int32_t tcps_preddat;		/* times hdr predict ok for data pkts */

	u_int32_t tcps_pcbhashmiss;	/* input packets missing pcb hash */
	u_int32_t tcps_noport;		/* no socket on port */
	u_int32_t tcps_badsyn;		/* SYN packet with src==dst rcv'ed */
	u_int32_t tcps_dropsyn;		/* SYN packet dropped */

	u_int32_t tcps_rcvbadsig;	/* rcvd bad/missing TCP signatures */
	u_int64_t tcps_rcvgoodsig;	/* rcvd good TCP signatures */
	u_int32_t tcps_inswcsum;	/* input software-checksummed packets */
	u_int32_t tcps_outswcsum;	/* output software-checksummed packets */

	/* ECN stats */
	u_int32_t tcps_ecn_accepts;	/* ecn connections accepted */
	u_int32_t tcps_ecn_rcvece;	/* # of rcvd ece */
	u_int32_t tcps_ecn_rcvcwr;	/* # of rcvd cwr */
	u_int32_t tcps_ecn_rcvce;	/* # of rcvd ce in ip header */
	u_int32_t tcps_ecn_sndect;	/* # of cwr sent */
	u_int32_t tcps_ecn_sndece;	/* # of ece sent */
	u_int32_t tcps_ecn_sndcwr;	/* # of cwr sent */
	u_int32_t tcps_cwr_ecn;		/* # of cwnd reduced by ecn */
	u_int32_t tcps_cwr_frecovery;	/* # of cwnd reduced by fastrecovery */
	u_int32_t tcps_cwr_timeout;	/* # of cwnd reduced by timeout */

	/* These statistics deal with the SYN cache. */
	u_int64_t tcps_sc_added;	/* # of entries added */
	u_int64_t tcps_sc_completed;	/* # of connections completed */
	u_int64_t tcps_sc_timed_out;	/* # of entries timed out */
	u_int64_t tcps_sc_overflowed;	/* # dropped due to overflow */
	u_int64_t tcps_sc_reset;	/* # dropped due to RST */
	u_int64_t tcps_sc_unreach;	/* # dropped due to ICMP unreach */
	u_int64_t tcps_sc_bucketoverflow;/* # dropped due to bucket overflow */
	u_int64_t tcps_sc_aborted;	/* # of entries aborted (no mem) */
	u_int64_t tcps_sc_dupesyn;	/* # of duplicate SYNs received */
	u_int64_t tcps_sc_dropped;	/* # of SYNs dropped (no route/mem) */
	u_int64_t tcps_sc_collisions;	/* # of hash collisions */
	u_int64_t tcps_sc_retransmitted;/* # of retransmissions */
	u_int64_t tcps_sc_seedrandom;	/* # of syn cache seeds with random */
	u_int64_t tcps_sc_hash_size;	/* hash buckets in current syn cache */
	u_int64_t tcps_sc_entry_count;	/* # of entries in current syn cache */
	u_int64_t tcps_sc_entry_limit;	/* limit of syn cache entries */
	u_int64_t tcps_sc_bucket_maxlen;/* maximum # of entries in any bucket */
	u_int64_t tcps_sc_bucket_limit;	/* limit of syn cache bucket list */
	u_int64_t tcps_sc_uses_left;	/* use counter of current syn cache */

	u_int64_t tcps_conndrained;	/* # of connections drained */

	u_int64_t tcps_sack_recovery_episode;	/* SACK recovery episodes */
	u_int64_t tcps_sack_rexmits;		/* SACK rexmit segments */
	u_int64_t tcps_sack_rexmit_bytes;	/* SACK rexmit bytes */
	u_int64_t tcps_sack_rcv_opts;		/* SACK options received */
	u_int64_t tcps_sack_snd_opts;		/* SACK options sent */
};

/*
 * Names for TCP sysctl objects.
 */

#define	TCPCTL_RFC1323		1 /* enable/disable RFC1323 timestamps/scaling */
#define	TCPCTL_KEEPINITTIME	2 /* TCPT_KEEP value */
#define TCPCTL_KEEPIDLE		3 /* allow tcp_keepidle to be changed */
#define TCPCTL_KEEPINTVL	4 /* allow tcp_keepintvl to be changed */
#define TCPCTL_SLOWHZ		5 /* return kernel idea of PR_SLOWHZ */
#define TCPCTL_BADDYNAMIC	6 /* return bad dynamic port bitmap */
#define	TCPCTL_RECVSPACE	7 /* receive buffer space */
#define	TCPCTL_SENDSPACE	8 /* send buffer space */
#define	TCPCTL_IDENT		9 /* get connection owner */
#define	TCPCTL_SACK	       10 /* selective acknowledgement, rfc 2018 */
#define TCPCTL_MSSDFLT	       11 /* Default maximum segment size */
#define	TCPCTL_RSTPPSLIMIT     12 /* RST pps limit */
#define	TCPCTL_ACK_ON_PUSH     13 /* ACK immediately on PUSH */
#define	TCPCTL_ECN	       14 /* RFC3168 ECN */
#define	TCPCTL_SYN_CACHE_LIMIT 15 /* max size of comp. state engine */
#define	TCPCTL_SYN_BUCKET_LIMIT	16 /* max size of hash bucket */
#define	TCPCTL_RFC3390	       17 /* enable/disable RFC3390 increased cwnd */
#define	TCPCTL_REASS_LIMIT     18 /* max entries for tcp reass queues */
#define	TCPCTL_DROP	       19 /* drop tcp connection */
#define	TCPCTL_SACKHOLE_LIMIT  20 /* max entries for tcp sack queues */
#define	TCPCTL_STATS	       21 /* TCP statistics */
#define	TCPCTL_ALWAYS_KEEPALIVE 22 /* assume SO_KEEPALIVE is always set */
#define	TCPCTL_SYN_USE_LIMIT   23 /* number of uses before reseeding hash */
#define TCPCTL_ROOTONLY	       24 /* return root only port bitmap */
#define	TCPCTL_SYN_HASH_SIZE   25 /* number of buckets in the hash */
#define	TCPCTL_MAXID	       26

#define	TCPCTL_NAMES { \
	{ 0, 0 }, \
	{ "rfc1323",	CTLTYPE_INT }, \
	{ "keepinittime",	CTLTYPE_INT }, \
	{ "keepidle",	CTLTYPE_INT }, \
	{ "keepintvl",	CTLTYPE_INT }, \
	{ "slowhz",	CTLTYPE_INT }, \
	{ "baddynamic", CTLTYPE_STRUCT }, \
	{ NULL,	0 }, \
	{ NULL,	0 }, \
	{ "ident", 	CTLTYPE_STRUCT }, \
	{ "sack",	CTLTYPE_INT }, \
	{ "mssdflt",	CTLTYPE_INT }, \
	{ "rstppslimit",	CTLTYPE_INT }, \
	{ "ackonpush",	CTLTYPE_INT }, \
	{ "ecn", 	CTLTYPE_INT }, \
	{ "syncachelimit", 	CTLTYPE_INT }, \
	{ "synbucketlimit", 	CTLTYPE_INT }, \
	{ "rfc3390", 	CTLTYPE_INT }, \
	{ "reasslimit", 	CTLTYPE_INT }, \
	{ "drop", 	CTLTYPE_STRUCT }, \
	{ "sackholelimit", 	CTLTYPE_INT }, \
	{ "stats",	CTLTYPE_STRUCT }, \
	{ "always_keepalive",	CTLTYPE_INT }, \
	{ "synuselimit", 	CTLTYPE_INT }, \
	{ "rootonly", CTLTYPE_STRUCT }, \
	{ "synhashsize", 	CTLTYPE_INT }, \
}

#define	TCPCTL_VARS { \
	NULL, \
	&tcp_do_rfc1323, \
	&tcptv_keep_init, \
	&tcp_keepidle, \
	&tcp_keepintvl, \
	NULL, \
	NULL, \
	NULL, \
	NULL, \
	NULL, \
	NULL, \
	&tcp_mssdflt, \
	&tcp_rst_ppslim, \
	&tcp_ack_on_push, \
	NULL, \
	&tcp_syn_cache_limit, \
	&tcp_syn_bucket_limit, \
	&tcp_do_rfc3390, \
	NULL, \
	NULL, \
	NULL, \
	NULL, \
	NULL, \
	NULL, \
	NULL, \
	NULL \
}

struct tcp_ident_mapping {
	struct sockaddr_storage faddr, laddr;
	int euid, ruid;
	u_int rdomain;
};

#ifdef _KERNEL

#include <sys/percpu.h>

enum tcpstat_counters {
	tcps_connattempt,
	tcps_accepts,
	tcps_connects,
	tcps_drops,
	tcps_conndrops,
	tcps_closed,
	tcps_segstimed,
	tcps_rttupdated,
	tcps_delack,
	tcps_timeoutdrop,
	tcps_rexmttimeo,
	tcps_persisttimeo,
	tcps_persistdrop,
	tcps_keeptimeo,
	tcps_keepprobe,
	tcps_keepdrops,
	tcps_sndtotal,
	tcps_sndpack,
	tcps_sndbyte,
	tcps_sndrexmitpack,
	tcps_sndrexmitbyte,
	tcps_sndrexmitfast,
	tcps_sndacks,
	tcps_sndprobe,
	tcps_sndurg,
	tcps_sndwinup,
	tcps_sndctrl,
	tcps_rcvtotal,
	tcps_rcvpack,
	tcps_rcvbyte,
	tcps_rcvbadsum,
	tcps_rcvbadoff,
	tcps_rcvmemdrop,
	tcps_rcvnosec,
	tcps_rcvshort,
	tcps_rcvduppack,
	tcps_rcvdupbyte,
	tcps_rcvpartduppack,
	tcps_rcvpartdupbyte,
	tcps_rcvoopack,
	tcps_rcvoobyte,
	tcps_rcvpackafterwin,
	tcps_rcvbyteafterwin,
	tcps_rcvafterclose,
	tcps_rcvwinprobe,
	tcps_rcvdupack,
	tcps_rcvacktoomuch,
	tcps_rcvacktooold,
	tcps_rcvackpack,
	tcps_rcvackbyte,
	tcps_rcvwinupd,
	tcps_pawsdrop,
	tcps_predack,
	tcps_preddat,
	tcps_pcbhashmiss,
	tcps_noport,
	tcps_badsyn,
	tcps_dropsyn,
	tcps_rcvbadsig,
	tcps_rcvgoodsig,
	tcps_inswcsum,
	tcps_outswcsum,
	tcps_ecn_accepts,
	tcps_ecn_rcvece,
	tcps_ecn_rcvcwr,
	tcps_ecn_rcvce,
	tcps_ecn_sndect,
	tcps_ecn_sndece,
	tcps_ecn_sndcwr,
	tcps_cwr_ecn,
	tcps_cwr_frecovery,
	tcps_cwr_timeout,
	tcps_sc_added,
	tcps_sc_completed,
	tcps_sc_timed_out,
	tcps_sc_overflowed,
	tcps_sc_reset,
	tcps_sc_unreach,
	tcps_sc_bucketoverflow,
	tcps_sc_aborted,
	tcps_sc_dupesyn,
	tcps_sc_dropped,
	tcps_sc_collisions,
	tcps_sc_retransmitted,
	tcps_sc_seedrandom,
	tcps_sc_hash_size,
	tcps_sc_entry_count,
	tcps_sc_entry_limit,
	tcps_sc_bucket_maxlen,
	tcps_sc_bucket_limit,
	tcps_sc_uses_left,
	tcps_conndrained,
	tcps_sack_recovery_episode,
	tcps_sack_rexmits,
	tcps_sack_rexmit_bytes,
	tcps_sack_rcv_opts,
	tcps_sack_snd_opts,
	tcps_ncounters,
};

extern struct cpumem *tcpcounters;

static inline void
tcpstat_inc(enum tcpstat_counters c)
{
	counters_inc(tcpcounters, c);
}

static inline void
tcpstat_add(enum tcpstat_counters c, uint64_t v)
{
	counters_add(tcpcounters, c, v);
}

static inline void
tcpstat_pkt(enum tcpstat_counters pcounter, enum tcpstat_counters bcounter,
    uint64_t v)
{
	counters_pkt(tcpcounters, pcounter, bcounter, v);
}

extern	struct inpcbtable tcbtable;	/* head of queue of active tcpcb's */
extern	u_int32_t tcp_now;		/* for RFC 1323 timestamps */
extern	int tcp_do_rfc1323;	/* enabled/disabled? */
extern	int tcptv_keep_init;	/* time to keep alive the initial SYN packet */
extern	int tcp_mssdflt;	/* default maximum segment size */
extern	int tcp_rst_ppslim;	/* maximum outgoing RST packet per second */
extern	int tcp_ack_on_push;	/* ACK immediately on PUSH */
#ifdef TCP_SACK
extern	int tcp_do_sack;	/* SACK enabled/disabled */
extern	struct pool sackhl_pool;
extern	int tcp_sackhole_limit;	/* max entries for tcp sack queues */
#endif
extern	int tcp_do_ecn;		/* RFC3168 ECN enabled/disabled? */
extern	int tcp_do_rfc3390;	/* RFC3390 Increasing TCP's Initial Window */

extern	struct pool tcpqe_pool;
extern	int tcp_reass_limit;	/* max entries for tcp reass queues */

extern	int tcp_syn_hash_size;  /* adjustable size of the hash array */
extern	int tcp_syn_cache_limit; /* max entries for compressed state engine */
extern	int tcp_syn_bucket_limit;/* max entries per hash bucket */
extern	int tcp_syn_use_limit;   /* number of uses before reseeding hash */
extern	struct syn_cache_set tcp_syn_cache[];
extern	int tcp_syn_cache_active; /* active syn cache, may be 0 or 1 */

int	 tcp_attach(struct socket *);
void	 tcp_canceltimers(struct tcpcb *);
struct tcpcb *
	 tcp_close(struct tcpcb *);
void	 tcp_reaper(void *);
int	 tcp_freeq(struct tcpcb *);
#ifdef INET6
void	 tcp6_ctlinput(int, struct sockaddr *, u_int, void *);
#endif
void	 tcp_ctlinput(int, struct sockaddr *, u_int, void *);
int	 tcp_ctloutput(int, struct socket *, int, int, struct mbuf *);
struct tcpcb *
	 tcp_disconnect(struct tcpcb *);
struct tcpcb *
	 tcp_drop(struct tcpcb *, int);
int	 tcp_dooptions(struct tcpcb *, u_char *, int, struct tcphdr *,
		struct mbuf *, int, struct tcp_opt_info *, u_int);
void	 tcp_init(void);
int	 tcp_input(struct mbuf **, int *, int);
int	 tcp_mss(struct tcpcb *, int);
void	 tcp_mss_update(struct tcpcb *);
u_int	 tcp_hdrsz(struct tcpcb *);
void	 tcp_mtudisc(struct inpcb *, int);
void	 tcp_mtudisc_increase(struct inpcb *, int);
#ifdef INET6
void	tcp6_mtudisc(struct inpcb *, int);
void	tcp6_mtudisc_callback(struct sockaddr_in6 *, u_int);
#endif
struct tcpcb *
	 tcp_newtcpcb(struct inpcb *);
void	 tcp_notify(struct inpcb *, int);
int	 tcp_output(struct tcpcb *);
void	 tcp_pulloutofband(struct socket *, u_int, struct mbuf *, int);
int	 tcp_reass(struct tcpcb *, struct tcphdr *, struct mbuf *, int *);
void	 tcp_rscale(struct tcpcb *, u_long);
void	 tcp_respond(struct tcpcb *, caddr_t, struct tcphdr *, tcp_seq,
		tcp_seq, int, u_int);
void	 tcp_setpersist(struct tcpcb *);
void	 tcp_update_sndspace(struct tcpcb *);
void	 tcp_update_rcvspace(struct tcpcb *);
void	 tcp_slowtimo(void);
struct mbuf *
	 tcp_template(struct tcpcb *);
void	 tcp_trace(short, short, struct tcpcb *, caddr_t, int, int);
struct tcpcb *
	 tcp_usrclosed(struct tcpcb *);
int	 tcp_sysctl(int *, u_int, void *, size_t *, void *, size_t);
int	 tcp_usrreq(struct socket *,
	    int, struct mbuf *, struct mbuf *, struct mbuf *, struct proc *);
void	 tcp_xmit_timer(struct tcpcb *, int);
void	 tcpdropoldhalfopen(struct tcpcb *, u_int16_t);
#ifdef TCP_SACK
void	 tcp_sack_option(struct tcpcb *,struct tcphdr *,u_char *,int);
void	 tcp_update_sack_list(struct tcpcb *tp, tcp_seq, tcp_seq);
void	 tcp_del_sackholes(struct tcpcb *, struct tcphdr *);
void	 tcp_clean_sackreport(struct tcpcb *tp);
void	 tcp_sack_adjust(struct tcpcb *tp);
struct sackhole *
	 tcp_sack_output(struct tcpcb *tp);
int	 tcp_sack_partialack(struct tcpcb *, struct tcphdr *);
#ifdef DEBUG
void	 tcp_print_holes(struct tcpcb *tp);
#endif
#endif /* TCP_SACK */
#if defined(TCP_SACK)
int	 tcp_newreno(struct tcpcb *, struct tcphdr *);
u_long	 tcp_seq_subtract(u_long, u_long );
#endif /* TCP_SACK */
#ifdef TCP_SIGNATURE
int	tcp_signature_apply(caddr_t, caddr_t, unsigned int);
int	tcp_signature(struct tdb *, int, struct mbuf *, struct tcphdr *,
	    int, int, char *);
#endif /* TCP_SIGNATURE */
void     tcp_set_iss_tsm(struct tcpcb *);

void	 syn_cache_unreach(struct sockaddr *, struct sockaddr *,
	   struct tcphdr *, u_int);
void	 syn_cache_init(void);
void	 syn_cache_cleanup(struct tcpcb *);

#endif /* _KERNEL */
#endif /* _NETINET_TCP_VAR_H_ */