/
tcp_var.h
942 lines (864 loc) · 35.5 KB
/
tcp_var.h
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
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
/* $NetBSD: tcp_var.h,v 1.150 2007/08/02 02:42:42 rmind Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* 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 project 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 PROJECT 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 PROJECT 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.
*/
/*
* @(#)COPYRIGHT 1.1 (NRL) 17 January 1995
*
* NRL grants permission for redistribution and use in source and binary
* forms, with or without modification, of the software and documentation
* created at NRL 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgements:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* This product includes software developed at the Information
* Technology Division, US Naval Research Laboratory.
* 4. Neither the name of the NRL nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THE SOFTWARE PROVIDED BY NRL IS PROVIDED BY NRL 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 NRL 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.
*
* The views and conclusions contained in the software and documentation
* are those of the authors and should not be interpreted as representing
* official policies, either expressed or implied, of the US Naval
* Research Laboratory (NRL).
*/
/*-
* Copyright (c) 1997, 1998, 1999, 2001, 2005 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center.
* This code is derived from software contributed to The NetBSD Foundation
* by Charles M. Hannum.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* Copyright (c) 1982, 1986, 1993, 1994, 1995
* 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 8.4 (Berkeley) 5/24/95
*/
#ifndef _NETINET_TCP_VAR_H_
#define _NETINET_TCP_VAR_H_
#if defined(_KERNEL_OPT)
#include "opt_inet.h"
#include "opt_mbuftrace.h"
#include "rnd.h"
#endif
/*
* Kernel variables for tcp.
*/
#include <sys/callout.h>
#ifdef TCP_SIGNATURE
/*
* Defines which are needed by the xform_tcp module and tcp_[in|out]put
* for SADB verification and lookup.
*/
#define TCP_SIGLEN 16 /* length of computed digest in bytes */
#define TCP_KEYLEN_MIN 1 /* minimum length of TCP-MD5 key */
#define TCP_KEYLEN_MAX 80 /* maximum length of TCP-MD5 key */
/*
* Only a single SA per host may be specified at this time. An SPI is
* needed in order for the KEY_ALLOCSA() lookup to work.
*/
#define TCP_SIG_SPI 0x1000
#endif /* TCP_SIGNATURE */
/*
* SACK option block.
*/
struct sackblk {
tcp_seq left; /* Left edge of sack block. */
tcp_seq right; /* Right edge of sack block. */
};
TAILQ_HEAD(sackhead, sackhole);
struct sackhole {
tcp_seq start;
tcp_seq end;
tcp_seq rxmit;
TAILQ_ENTRY(sackhole) sackhole_q;
};
/*
* Tcp control block, one per tcp; fields:
*/
struct tcpcb {
int t_family; /* address family on the wire */
struct ipqehead segq; /* sequencing queue */
int t_segqlen; /* length of the above */
callout_t t_timer[TCPT_NTIMERS];/* tcp timers */
short t_state; /* state of this connection */
short t_rxtshift; /* log(2) of rexmt exp. backoff */
uint32_t t_rxtcur; /* current retransmit value */
short t_dupacks; /* consecutive dup acks recd */
short t_partialacks; /* partials acks during fast rexmit */
u_short t_peermss; /* peer's maximum segment size */
u_short t_ourmss; /* our's maximum segment size */
u_short t_segsz; /* current segment size in use */
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_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_SYN_REXMT 0x0400 /* rexmit timer fired on SYN */
#define TF_WILL_SACK 0x0800 /* try to use SACK */
#define TF_REASSEMBLING 0x1000 /* we're busy reassembling */
#define TF_DEAD 0x2000 /* dead and to-be-released */
#define TF_PMTUD_PEND 0x4000 /* Path MTU Discovery pending */
#define TF_ECN_PERMIT 0x10000 /* other side said is ECN-ready */
#define TF_ECN_SND_CWR 0x20000 /* ECN CWR in queue */
#define TF_ECN_SND_ECE 0x40000 /* ECN ECE in queue */
#define TF_SIGNATURE 0x400000 /* require MD5 digests (RFC2385) */
struct mbuf *t_template; /* skeletal packet for transmit */
struct inpcb *t_inpcb; /* back pointer to internet pcb */
struct in6pcb *t_in6pcb; /* back pointer to internet pcb */
callout_t t_delack_ch; /* delayed ACK callout */
/*
* 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 */
tcp_seq snd_recover; /* for use in fast recovery */
tcp_seq snd_high; /* NewReno false fast rexmit seq */
/* 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 */
/*
* 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 threshhold for
* for slow start exponential to
* linear switch
*/
/* auto-sizing variables */
u_int rfbuf_cnt; /* recv buffer autoscaling byte count */
uint32_t rfbuf_ts; /* recv buffer autoscaling timestamp */
/*
* 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 */
int32_t t_srtt; /* smoothed round-trip time */
int32_t t_rttvar; /* variance in round-trip time */
uint32_t 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_recent_age; /* when last updated */
u_int32_t ts_timebase; /* our timebase */
tcp_seq last_ack_sent;
/* RFC 3465 variables */
u_long t_bytes_acked; /* ABC "bytes_acked" parameter */
/* SACK stuff */
#define TCP_SACK_MAX 3
#define TCPSACK_NONE 0
#define TCPSACK_HAVED 1
u_char rcv_sack_flags; /* SACK flags. */
struct sackblk rcv_dsack_block; /* RX D-SACK block. */
struct ipqehead timeq; /* time sequenced queue. */
struct sackhead snd_holes; /* TX SACK holes. */
int snd_numholes; /* Number of TX SACK holes. */
tcp_seq rcv_lastsack; /* last seq number(+1) sack'd by rcv'r*/
tcp_seq sack_newdata; /* New data xmitted in this recovery
episode starts at this seq number*/
tcp_seq snd_fack; /* FACK TCP. Forward-most data held by
peer. */
/* pointer for syn cache entries*/
LIST_HEAD(, syn_cache) t_sc; /* list of entries by this tcb */
/* prediction of next mbuf when using large window sizes */
struct mbuf *t_lastm; /* last mbuf that data was sent from */
int t_inoff; /* data offset in previous mbuf */
int t_lastoff; /* last data address in mbuf chain */
int t_lastlen; /* last length read from mbuf chain */
/* Path-MTU discovery blackhole detection */
int t_mtudisc; /* perform mtudisc for 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 */
uint8_t t_ecn_retries; /* # of ECN setup retries */
struct tcp_congctl *t_congctl; /* per TCB congctl algorithm */
/* Keepalive per socket */
u_int t_keepinit;
u_int t_keepidle;
u_int t_keepintvl;
u_int t_keepcnt;
u_int t_maxidle; /* t_keepcnt * t_keepintvl */
};
/*
* Macros to aid ECN TCP.
*/
#define TCP_ECN_ALLOWED(tp) (tp->t_flags & TF_ECN_PERMIT)
/*
* Macros to aid SACK/FACK TCP.
*/
#define TCP_SACK_ENABLED(tp) (tp->t_flags & TF_WILL_SACK)
#define TCP_FACK_FASTRECOV(tp) \
(TCP_SACK_ENABLED(tp) && \
(SEQ_GT(tp->snd_fack, tp->snd_una + tcprexmtthresh * tp->t_segsz)))
#ifdef _KERNEL
/*
* TCP reassembly queue locks.
*/
static __inline int tcp_reass_lock_try (struct tcpcb *)
__attribute__((__unused__));
static __inline void tcp_reass_unlock (struct tcpcb *)
__attribute__((__unused__));
static __inline int
tcp_reass_lock_try(tp)
struct tcpcb *tp;
{
int s;
/*
* Use splvm() -- we're blocking things that would cause
* mbuf allocation.
*/
s = splvm();
if (tp->t_flags & TF_REASSEMBLING) {
splx(s);
return (0);
}
tp->t_flags |= TF_REASSEMBLING;
splx(s);
return (1);
}
static __inline void
tcp_reass_unlock(tp)
struct tcpcb *tp;
{
int s;
s = splvm();
tp->t_flags &= ~TF_REASSEMBLING;
splx(s);
}
#ifdef DIAGNOSTIC
#define TCP_REASS_LOCK(tp) \
do { \
if (tcp_reass_lock_try(tp) == 0) { \
printf("%s:%d: tcpcb %p reass already locked\n", \
__FILE__, __LINE__, tp); \
panic("tcp_reass_lock"); \
} \
} while (/*CONSTCOND*/ 0)
#define TCP_REASS_LOCK_CHECK(tp) \
do { \
if (((tp)->t_flags & TF_REASSEMBLING) == 0) { \
printf("%s:%d: tcpcb %p reass lock not held\n", \
__FILE__, __LINE__, tp); \
panic("tcp reass lock check"); \
} \
} while (/*CONSTCOND*/ 0)
#else
#define TCP_REASS_LOCK(tp) (void) tcp_reass_lock_try((tp))
#define TCP_REASS_LOCK_CHECK(tp) /* nothing */
#endif
#define TCP_REASS_UNLOCK(tp) tcp_reass_unlock((tp))
#endif /* _KERNEL */
/*
* Queue for delayed ACK processing.
*/
#ifdef _KERNEL
extern int tcp_delack_ticks;
void tcp_delack(void *);
#define TCP_RESTART_DELACK(tp) \
callout_reset(&(tp)->t_delack_ch, tcp_delack_ticks, \
tcp_delack, tp)
#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; \
callout_stop(&(tp)->t_delack_ch); \
} \
} while (/*CONSTCOND*/0)
#endif /* _KERNEL */
/*
* Compute the current timestamp for a connection.
*/
#define TCP_TIMESTAMP(tp) (tcp_now - (tp)->ts_timebase)
/*
* 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;
};
#define TOF_SIGNATURE 0x0040 /* signature option present */
#define TOF_SIGLEN 0x0080 /* sigature length valid (RFC2385) */
/*
* Data for the TCP compressed state engine.
*/
union syn_cache_sa {
struct sockaddr sa;
struct sockaddr_in sin;
#if 1 /*def INET6*/
struct sockaddr_in6 sin6;
#endif
};
struct syn_cache {
TAILQ_ENTRY(syn_cache) sc_bucketq; /* link on bucket list */
callout_t sc_timer; /* rexmt timer */
struct route sc_route;
long sc_win; /* advertised window */
int sc_bucketidx; /* our bucket index */
u_int32_t sc_hash;
u_int32_t sc_timestamp; /* timestamp from SYN */
u_int32_t sc_timebase; /* our local timebase */
union syn_cache_sa sc_src;
union syn_cache_sa sc_dst;
tcp_seq sc_irs;
tcp_seq sc_iss;
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 /* peer will do SACK */
#define SCF_ECN_PERMIT 0x0010 /* peer will do ECN */
#define SCF_SIGNATURE 0x40 /* send MD5 digests */
struct mbuf *sc_ipopts; /* IP options */
u_int16_t sc_peermaxseg;
u_int16_t sc_ourmaxseg;
u_int8_t 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 */
};
#define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb)
#ifdef INET6
#define in6totcpcb(ip) ((struct tcpcb *)(ip)->in6p_ppcb)
#endif
#ifndef INET6
#define sototcpcb(so) (intotcpcb(sotoinpcb(so)))
#else
#define sototcpcb(so) (((so)->so_proto->pr_domain->dom_family == AF_INET) \
? intotcpcb(sotoinpcb(so)) \
: in6totcpcb(sotoin6pcb(so)))
#endif
/*
* 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 3 bits to the right of the binary point,
* and thus an "ALPHA" of 0.875. rttvar has 2 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; 3 bits frac. */
#define TCP_RTTVAR_SHIFT 2 /* multiplier for rttvar; 2 bits */
/*
* 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) >> 2)
/*
* Compute the initial window for slow start.
*/
#define TCP_INITIAL_WINDOW(iw, segsz) \
(((iw) == 0) ? (min(4 * (segsz), max(2 * (segsz), 4380))) : \
((segsz) * (iw)))
/*
* TCP statistics.
* Many of these should be kept per connection,
* but that's inconvenient at the moment.
*/
struct tcpstat {
u_quad_t tcps_connattempt; /* connections initiated */
u_quad_t tcps_accepts; /* connections accepted */
u_quad_t tcps_connects; /* connections established */
u_quad_t tcps_drops; /* connections dropped */
u_quad_t tcps_conndrops; /* embryonic connections dropped */
u_quad_t tcps_closed; /* conn. closed (includes drops) */
u_quad_t tcps_segstimed; /* segs where we tried to get rtt */
u_quad_t tcps_rttupdated; /* times we succeeded */
u_quad_t tcps_delack; /* delayed acks sent */
u_quad_t tcps_timeoutdrop; /* conn. dropped in rxmt timeout */
u_quad_t tcps_rexmttimeo; /* retransmit timeouts */
u_quad_t tcps_persisttimeo; /* persist timeouts */
u_quad_t tcps_keeptimeo; /* keepalive timeouts */
u_quad_t tcps_keepprobe; /* keepalive probes sent */
u_quad_t tcps_keepdrops; /* connections dropped in keepalive */
u_quad_t tcps_persistdrops; /* connections dropped in persist */
u_quad_t tcps_connsdrained; /* connections drained due to memory
shortage */
u_quad_t tcps_pmtublackhole; /* PMTUD blackhole detected */
u_quad_t tcps_sndtotal; /* total packets sent */
u_quad_t tcps_sndpack; /* data packets sent */
u_quad_t tcps_sndbyte; /* data bytes sent */
u_quad_t tcps_sndrexmitpack; /* data packets retransmitted */
u_quad_t tcps_sndrexmitbyte; /* data bytes retransmitted */
u_quad_t tcps_sndacks; /* ack-only packets sent */
u_quad_t tcps_sndprobe; /* window probes sent */
u_quad_t tcps_sndurg; /* packets sent with URG only */
u_quad_t tcps_sndwinup; /* window update-only packets sent */
u_quad_t tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */
u_quad_t tcps_rcvtotal; /* total packets received */
u_quad_t tcps_rcvpack; /* packets received in sequence */
u_quad_t tcps_rcvbyte; /* bytes received in sequence */
u_quad_t tcps_rcvbadsum; /* packets received with ccksum errs */
u_quad_t tcps_rcvbadoff; /* packets received with bad offset */
u_quad_t tcps_rcvmemdrop; /* packets dropped for lack of memory */
u_quad_t tcps_rcvshort; /* packets received too short */
u_quad_t tcps_rcvduppack; /* duplicate-only packets received */
u_quad_t tcps_rcvdupbyte; /* duplicate-only bytes received */
u_quad_t tcps_rcvpartduppack; /* packets with some duplicate data */
u_quad_t tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */
u_quad_t tcps_rcvoopack; /* out-of-order packets received */
u_quad_t tcps_rcvoobyte; /* out-of-order bytes received */
u_quad_t tcps_rcvpackafterwin; /* packets with data after window */
u_quad_t tcps_rcvbyteafterwin; /* bytes rcvd after window */
u_quad_t tcps_rcvafterclose; /* packets rcvd after "close" */
u_quad_t tcps_rcvwinprobe; /* rcvd window probe packets */
u_quad_t tcps_rcvdupack; /* rcvd duplicate acks */
u_quad_t tcps_rcvacktoomuch; /* rcvd acks for unsent data */
u_quad_t tcps_rcvackpack; /* rcvd ack packets */
u_quad_t tcps_rcvackbyte; /* bytes acked by rcvd acks */
u_quad_t tcps_rcvwinupd; /* rcvd window update packets */
u_quad_t tcps_pawsdrop; /* segments dropped due to PAWS */
u_quad_t tcps_predack; /* times hdr predict ok for acks */
u_quad_t tcps_preddat; /* times hdr predict ok for data pkts */
u_quad_t tcps_pcbhashmiss; /* input packets missing pcb hash */
u_quad_t tcps_noport; /* no socket on port */
u_quad_t tcps_badsyn; /* received ack for which we have
no SYN in compressed state */
u_quad_t tcps_delayed_free; /* delayed pool_put() of tcpcb */
/* These statistics deal with the SYN cache. */
u_quad_t tcps_sc_added; /* # of entries added */
u_quad_t tcps_sc_completed; /* # of connections completed */
u_quad_t tcps_sc_timed_out; /* # of entries timed out */
u_quad_t tcps_sc_overflowed; /* # dropped due to overflow */
u_quad_t tcps_sc_reset; /* # dropped due to RST */
u_quad_t tcps_sc_unreach; /* # dropped due to ICMP unreach */
u_quad_t tcps_sc_bucketoverflow;/* # dropped due to bucket overflow */
u_quad_t tcps_sc_aborted; /* # of entries aborted (no mem) */
u_quad_t tcps_sc_dupesyn; /* # of duplicate SYNs received */
u_quad_t tcps_sc_dropped; /* # of SYNs dropped (no route/mem) */
u_quad_t tcps_sc_collisions; /* # of hash collisions */
u_quad_t tcps_sc_retransmitted; /* # of retransmissions */
u_quad_t tcps_sc_delayed_free; /* # of delayed pool_put()s */
u_quad_t tcps_selfquench; /* # of ENOBUFS we get on output */
u_quad_t tcps_badsig; /* # of drops due to bad signature */
u_quad_t tcps_goodsig; /* # of packets with good signature */
u_quad_t tcps_ecn_shs; /* # of sucessful ECN handshakes */
u_quad_t tcps_ecn_ce; /* # of packets with CE bit */
u_quad_t tcps_ecn_ect; /* # of packets with ECT(0) bit */
};
/*
* Names for TCP sysctl objects.
*/
#define TCPCTL_RFC1323 1 /* RFC1323 timestamps/scaling */
#define TCPCTL_SENDSPACE 2 /* default send buffer */
#define TCPCTL_RECVSPACE 3 /* default recv buffer */
#define TCPCTL_MSSDFLT 4 /* default seg size */
#define TCPCTL_SYN_CACHE_LIMIT 5 /* max size of comp. state engine */
#define TCPCTL_SYN_BUCKET_LIMIT 6 /* max size of hash bucket */
#if 0 /*obsoleted*/
#define TCPCTL_SYN_CACHE_INTER 7 /* interval of comp. state timer */
#endif
#define TCPCTL_INIT_WIN 8 /* initial window */
#define TCPCTL_MSS_IFMTU 9 /* mss from interface, not in_maxmtu */
#define TCPCTL_SACK 10 /* RFC2018 selective acknowledgement */
#define TCPCTL_WSCALE 11 /* RFC1323 window scaling */
#define TCPCTL_TSTAMP 12 /* RFC1323 timestamps */
#define TCPCTL_COMPAT_42 13 /* 4.2BSD TCP bug work-arounds */
#define TCPCTL_CWM 14 /* Congestion Window Monitoring */
#define TCPCTL_CWM_BURSTSIZE 15 /* burst size allowed by CWM */
#define TCPCTL_ACK_ON_PUSH 16 /* ACK immediately on PUSH */
#define TCPCTL_KEEPIDLE 17 /* keepalive idle time */
#define TCPCTL_KEEPINTVL 18 /* keepalive probe interval */
#define TCPCTL_KEEPCNT 19 /* keepalive count */
#define TCPCTL_SLOWHZ 20 /* PR_SLOWHZ (read-only) */
#define TCPCTL_NEWRENO 21 /* NewReno Congestion Control */
#define TCPCTL_LOG_REFUSED 22 /* Log refused connections */
#if 0 /*obsoleted*/
#define TCPCTL_RSTRATELIMIT 23 /* RST rate limit */
#endif
#define TCPCTL_RSTPPSLIMIT 24 /* RST pps limit */
#define TCPCTL_DELACK_TICKS 25 /* # ticks to delay ACK */
#define TCPCTL_INIT_WIN_LOCAL 26 /* initial window for local nets */
#define TCPCTL_IDENT 27 /* rfc 931 identd */
#define TCPCTL_ACKDROPRATELIMIT 28 /* SYN/RST -> ACK rate limit */
#define TCPCTL_LOOPBACKCKSUM 29 /* do TCP checksum on loopback */
#define TCPCTL_STATS 30 /* TCP statistics */
#define TCPCTL_DEBUG 31 /* TCP debug sockets */
#define TCPCTL_DEBX 32 /* # of tcp debug sockets */
#define TCPCTL_DROP 33 /* drop tcp connection */
#define TCPCTL_MAXID 34
#define TCPCTL_NAMES { \
{ 0, 0 }, \
{ "rfc1323", CTLTYPE_INT }, \
{ "sendspace", CTLTYPE_INT }, \
{ "recvspace", CTLTYPE_INT }, \
{ "mssdflt", CTLTYPE_INT }, \
{ "syn_cache_limit", CTLTYPE_INT }, \
{ "syn_bucket_limit", CTLTYPE_INT }, \
{ 0, 0 },\
{ "init_win", CTLTYPE_INT }, \
{ "mss_ifmtu", CTLTYPE_INT }, \
{ "sack", CTLTYPE_INT }, \
{ "win_scale", CTLTYPE_INT }, \
{ "timestamps", CTLTYPE_INT }, \
{ "compat_42", CTLTYPE_INT }, \
{ "cwm", CTLTYPE_INT }, \
{ "cwm_burstsize", CTLTYPE_INT }, \
{ "ack_on_push", CTLTYPE_INT }, \
{ "keepidle", CTLTYPE_INT }, \
{ "keepintvl", CTLTYPE_INT }, \
{ "keepcnt", CTLTYPE_INT }, \
{ "slowhz", CTLTYPE_INT }, \
{ 0, 0 }, \
{ "log_refused",CTLTYPE_INT }, \
{ 0, 0 }, \
{ "rstppslimit", CTLTYPE_INT }, \
{ "delack_ticks", CTLTYPE_INT }, \
{ "init_win_local", CTLTYPE_INT }, \
{ "ident", CTLTYPE_STRUCT }, \
{ "ackdropppslimit", CTLTYPE_INT }, \
{ "do_loopback_cksum", CTLTYPE_INT }, \
{ "stats", CTLTYPE_STRUCT }, \
{ "debug", CTLTYPE_STRUCT }, \
{ "debx", CTLTYPE_INT }, \
{ "drop", CTLTYPE_STRUCT }, \
}
#ifdef _KERNEL
extern struct inpcbtable tcbtable; /* head of queue of active tcpcb's */
extern struct tcpstat tcpstat; /* tcp statistics */
extern u_int32_t tcp_now; /* for RFC 1323 timestamps */
extern int tcp_do_rfc1323; /* enabled/disabled? */
extern int tcp_do_sack; /* SACK enabled/disabled? */
extern int tcp_do_win_scale; /* RFC1323 window scaling enabled/disabled? */
extern int tcp_do_timestamps; /* RFC1323 timestamps enabled/disabled? */
extern int tcp_mssdflt; /* default seg size */
extern int tcp_minmss; /* minimal seg size */
extern int tcp_init_win; /* initial window */
extern int tcp_init_win_local; /* initial window for local nets */
extern int tcp_mss_ifmtu; /* take MSS from interface, not in_maxmtu */
extern int tcp_compat_42; /* work around ancient broken TCP peers */
extern int tcp_cwm; /* enable Congestion Window Monitoring */
extern int tcp_cwm_burstsize; /* burst size allowed by CWM */
extern int tcp_ack_on_push; /* ACK immediately on PUSH */
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_log_refused; /* log refused connections */
extern int tcp_do_ecn; /* TCP ECN enabled/disabled? */
extern int tcp_ecn_maxretries; /* Max ECN setup retries */
#if NRND > 0
extern int tcp_do_rfc1948; /* ISS by cryptographic hash */
#endif
extern int tcp_sack_tp_maxholes; /* Max holes per connection. */
extern int tcp_sack_globalmaxholes; /* Max holes per system. */
extern int tcp_sack_globalholes; /* Number of holes present. */
extern int tcp_do_abc; /* RFC3465 ABC enabled/disabled? */
extern int tcp_abc_aggressive; /* 1: L=2*SMSS 0: L=1*SMSS */
extern int tcp_rst_ppslim;
extern int tcp_ackdrop_ppslim;
extern int tcp_syn_cache_size;
extern struct syn_cache_head tcp_syn_cache[];
extern u_long syn_cache_count;
#ifdef MBUFTRACE
extern struct mowner tcp_rx_mowner;
extern struct mowner tcp_tx_mowner;
extern struct mowner tcp_reass_mowner;
extern struct mowner tcp_sock_mowner;
extern struct mowner tcp_sock_rx_mowner;
extern struct mowner tcp_sock_tx_mowner;
extern struct mowner tcp_mowner;
#endif
extern int tcp_do_autorcvbuf;
extern int tcp_autorcvbuf_inc;
extern int tcp_autorcvbuf_max;
extern int tcp_do_autosndbuf;
extern int tcp_autosndbuf_inc;
extern int tcp_autosndbuf_max;
#define TCPCTL_VARIABLES { \
{ 0 }, \
{ 1, 0, &tcp_do_rfc1323 }, \
{ 1, 0, &tcp_sendspace }, \
{ 1, 0, &tcp_recvspace }, \
{ 1, 0, &tcp_mssdflt }, \
{ 1, 0, &tcp_syn_cache_limit }, \
{ 1, 0, &tcp_syn_bucket_limit }, \
{ 0 }, \
{ 1, 0, &tcp_init_win }, \
{ 1, 0, &tcp_mss_ifmtu }, \
{ 1, 0, &tcp_do_sack }, \
{ 1, 0, &tcp_do_win_scale }, \
{ 1, 0, &tcp_do_timestamps }, \
{ 1, 0, &tcp_compat_42 }, \
{ 1, 0, &tcp_cwm }, \
{ 1, 0, &tcp_cwm_burstsize }, \
{ 1, 0, &tcp_ack_on_push }, \
{ 1, 0, &tcp_keepidle }, \
{ 1, 0, &tcp_keepintvl }, \
{ 1, 0, &tcp_keepcnt }, \
{ 1, 1, 0, PR_SLOWHZ }, \
{ 0 }, \
{ 1, 0, &tcp_log_refused }, \
{ 0 }, \
{ 1, 0, &tcp_rst_ppslim }, \
{ 1, 0, &tcp_delack_ticks }, \
{ 1, 0, &tcp_init_win_local }, \
{ 1, 0, &tcp_ackdrop_ppslim }, \
}
#ifdef __NO_STRICT_ALIGNMENT
#define TCP_HDR_ALIGNED_P(th) 1
#else
#define TCP_HDR_ALIGNED_P(th) ((((vaddr_t)(th)) & 3) == 0)
#endif
struct secasvar;
int tcp_attach(struct socket *);
void tcp_canceltimers(struct tcpcb *);
int tcp_timers_invoking(struct tcpcb*);
struct tcpcb *
tcp_close(struct tcpcb *);
int tcp_isdead(struct tcpcb *);
#ifdef INET6
void tcp6_ctlinput(int, const struct sockaddr *, void *);
#endif
void *tcp_ctlinput(int, const struct sockaddr *, void *);
int tcp_ctloutput(int, struct socket *, int, int, struct mbuf **);
struct tcpcb *
tcp_disconnect(struct tcpcb *);
struct tcpcb *
tcp_drop(struct tcpcb *, int);
#ifdef TCP_SIGNATURE
int tcp_signature_apply(void *, void *, u_int);
struct secasvar *tcp_signature_getsav(struct mbuf *, struct tcphdr *);
int tcp_signature(struct mbuf *, struct tcphdr *, int, struct secasvar *,
char *);
#endif
void tcp_drain(void);
void tcp_established(struct tcpcb *);
void tcp_init(void);
#ifdef INET6
int tcp6_input(struct mbuf **, int *, int);
#endif
void tcp_input(struct mbuf *, ...);
u_int tcp_hdrsz(struct tcpcb *);
u_long tcp_mss_to_advertise(const struct ifnet *, int);
void tcp_mss_from_peer(struct tcpcb *, int);
void tcp_tcpcb_template(void);
struct tcpcb *
tcp_newtcpcb(int, void *);
void tcp_notify(struct inpcb *, int);
#ifdef INET6
void tcp6_notify(struct in6pcb *, int);
#endif
u_int tcp_optlen(struct tcpcb *);
int tcp_output(struct tcpcb *);
void tcp_pulloutofband(struct socket *,
struct tcphdr *, struct mbuf *, int);
void tcp_quench(struct inpcb *, int);
#ifdef INET6
void tcp6_quench(struct in6pcb *, int);
#endif
void tcp_mtudisc(struct inpcb *, int);
struct ipqent *tcpipqent_alloc(void);
void tcpipqent_free(struct ipqent *);
int tcp_respond(struct tcpcb *, struct mbuf *, struct mbuf *,
struct tcphdr *, tcp_seq, tcp_seq, int);
void tcp_rmx_rtt(struct tcpcb *);
void tcp_setpersist(struct tcpcb *);
#ifdef TCP_SIGNATURE
int tcp_signature_compute(struct mbuf *, struct tcphdr *, int, int,
int, u_char *, u_int);
#endif
void tcp_slowtimo(void);
struct mbuf *
tcp_template(struct tcpcb *);
void tcp_trace(short, short, struct tcpcb *, struct mbuf *, int);
struct tcpcb *
tcp_usrclosed(struct tcpcb *);
int tcp_usrreq(struct socket *,
int, struct mbuf *, struct mbuf *, struct mbuf *, struct lwp *);
void tcp_xmit_timer(struct tcpcb *, uint32_t);
tcp_seq tcp_new_iss(struct tcpcb *, tcp_seq);
tcp_seq tcp_new_iss1(void *, void *, u_int16_t, u_int16_t, size_t,
tcp_seq);
void tcp_new_dsack(struct tcpcb *, tcp_seq, u_int32_t);
void tcp_sack_option(struct tcpcb *, const struct tcphdr *,
const u_char *, int);
void tcp_del_sackholes(struct tcpcb *, const struct tcphdr *);
void tcp_free_sackholes(struct tcpcb *);
void tcp_sack_adjust(struct tcpcb *tp);
struct sackhole *tcp_sack_output(struct tcpcb *tp, int *sack_bytes_rexmt);
void tcp_sack_newack(struct tcpcb *, const struct tcphdr *);
int tcp_sack_numblks(const struct tcpcb *);
#define TCP_SACK_OPTLEN(nblks) ((nblks) * 8 + 2 + 2)
int syn_cache_add(struct sockaddr *, struct sockaddr *,
struct tcphdr *, unsigned int, struct socket *,
struct mbuf *, u_char *, int, struct tcp_opt_info *);
void syn_cache_unreach(const struct sockaddr *, const struct sockaddr *,
struct tcphdr *);
struct socket *syn_cache_get(struct sockaddr *, struct sockaddr *,
struct tcphdr *, unsigned int, unsigned int,
struct socket *so, struct mbuf *);
void syn_cache_init(void);
void syn_cache_insert(struct syn_cache *, struct tcpcb *);
struct syn_cache *syn_cache_lookup(const struct sockaddr *, const struct sockaddr *,
struct syn_cache_head **);
void syn_cache_reset(struct sockaddr *, struct sockaddr *,
struct tcphdr *);
int syn_cache_respond(struct syn_cache *, struct mbuf *);
void syn_cache_timer(void *);
void syn_cache_cleanup(struct tcpcb *);
int tcp_input_checksum(int, struct mbuf *, const struct tcphdr *, int, int,
int);
#endif
#endif /* !_NETINET_TCP_VAR_H_ */