FreeBSD/Linux Kernel Cross Reference
sys/netinet/tcp_var.h
1 /*-
2 * Copyright (c) 1982, 1986, 1993, 1994, 1995
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * @(#)tcp_var.h 8.4 (Berkeley) 5/24/95
30 * $FreeBSD$
31 */
32
33 #ifndef _NETINET_TCP_VAR_H_
34 #define _NETINET_TCP_VAR_H_
35
36 #include <netinet/tcp.h>
37
38 /*
39 * Kernel variables for tcp.
40 */
41 extern int tcp_do_rfc1323;
42 extern int tcp_do_rfc1644;
43
44 /* TCP segment queue entry */
45 struct tseg_qent {
46 LIST_ENTRY(tseg_qent) tqe_q;
47 int tqe_len; /* TCP segment data length */
48 struct tcphdr *tqe_th; /* a pointer to tcp header */
49 struct mbuf *tqe_m; /* mbuf contains packet */
50 };
51 LIST_HEAD(tsegqe_head, tseg_qent);
52 extern int tcp_reass_qsize;
53 extern struct uma_zone *tcp_reass_zone;
54
55 struct sackblk {
56 tcp_seq start; /* start seq no. of sack block */
57 tcp_seq end; /* end seq no. */
58 };
59
60 struct sackhole {
61 tcp_seq start; /* start seq no. of hole */
62 tcp_seq end; /* end seq no. */
63 tcp_seq rxmit; /* next seq. no in hole to be retransmitted */
64 struct sackhole *next; /* next in list */
65 };
66
67 struct tcptemp {
68 u_char tt_ipgen[40]; /* the size must be of max ip header, now IPv6 */
69 struct tcphdr tt_t;
70 };
71
72 #define tcp6cb tcpcb /* for KAME src sync over BSD*'s */
73
74 /*
75 * Tcp control block, one per tcp; fields:
76 * Organized for 16 byte cacheline efficiency.
77 */
78 struct tcpcb {
79 struct tsegqe_head t_segq; /* segment reassembly queue */
80 int t_segqlen; /* segment reassembly queue length */
81 int t_dupacks; /* consecutive dup acks recd */
82 struct tcptemp *unused; /* unused */
83
84 struct callout *tt_rexmt; /* retransmit timer */
85 struct callout *tt_persist; /* retransmit persistence */
86 struct callout *tt_keep; /* keepalive */
87 struct callout *tt_2msl; /* 2*msl TIME_WAIT timer */
88 struct callout *tt_delack; /* delayed ACK timer */
89
90 struct inpcb *t_inpcb; /* back pointer to internet pcb */
91 int t_state; /* state of this connection */
92 u_int t_flags;
93 #define TF_ACKNOW 0x000001 /* ack peer immediately */
94 #define TF_DELACK 0x000002 /* ack, but try to delay it */
95 #define TF_NODELAY 0x000004 /* don't delay packets to coalesce */
96 #define TF_NOOPT 0x000008 /* don't use tcp options */
97 #define TF_SENTFIN 0x000010 /* have sent FIN */
98 #define TF_REQ_SCALE 0x000020 /* have/will request window scaling */
99 #define TF_RCVD_SCALE 0x000040 /* other side has requested scaling */
100 #define TF_REQ_TSTMP 0x000080 /* have/will request timestamps */
101 #define TF_RCVD_TSTMP 0x000100 /* a timestamp was received in SYN */
102 #define TF_SACK_PERMIT 0x000200 /* other side said I could SACK */
103 #define TF_NEEDSYN 0x000400 /* send SYN (implicit state) */
104 #define TF_NEEDFIN 0x000800 /* send FIN (implicit state) */
105 #define TF_NOPUSH 0x001000 /* don't push */
106 #define TF_REQ_CC 0x002000 /* have/will request CC */
107 #define TF_RCVD_CC 0x004000 /* a CC was received in SYN */
108 #define TF_SENDCCNEW 0x008000 /* send CCnew instead of CC in SYN */
109 #define TF_MORETOCOME 0x010000 /* More data to be appended to sock */
110 #define TF_LQ_OVERFLOW 0x020000 /* listen queue overflow */
111 #define TF_LASTIDLE 0x040000 /* connection was previously idle */
112 #define TF_RXWIN0SENT 0x080000 /* sent a receiver win 0 in response */
113 #define TF_FASTRECOVERY 0x100000 /* in NewReno Fast Recovery */
114 #define TF_WASFRECOVERY 0x200000 /* was in NewReno Fast Recovery */
115 #define TF_SIGNATURE 0x400000 /* require MD5 digests (RFC2385) */
116 int t_force; /* 1 if forcing out a byte */
117
118 tcp_seq snd_una; /* send unacknowledged */
119 tcp_seq snd_max; /* highest sequence number sent;
120 * used to recognize retransmits
121 */
122 tcp_seq snd_nxt; /* send next */
123 tcp_seq snd_up; /* send urgent pointer */
124
125 tcp_seq snd_wl1; /* window update seg seq number */
126 tcp_seq snd_wl2; /* window update seg ack number */
127 tcp_seq iss; /* initial send sequence number */
128 tcp_seq irs; /* initial receive sequence number */
129
130 tcp_seq rcv_nxt; /* receive next */
131 tcp_seq rcv_adv; /* advertised window */
132 u_long rcv_wnd; /* receive window */
133 tcp_seq rcv_up; /* receive urgent pointer */
134
135 u_long snd_wnd; /* send window */
136 u_long snd_cwnd; /* congestion-controlled window */
137 u_long snd_bwnd; /* bandwidth-controlled window */
138 u_long snd_ssthresh; /* snd_cwnd size threshold for
139 * for slow start exponential to
140 * linear switch
141 */
142 u_long snd_bandwidth; /* calculated bandwidth or 0 */
143 tcp_seq snd_recover; /* for use in NewReno Fast Recovery */
144
145 u_int t_maxopd; /* mss plus options */
146
147 u_long t_rcvtime; /* inactivity time */
148 u_long t_starttime; /* time connection was established */
149 int t_rtttime; /* round trip time */
150 tcp_seq t_rtseq; /* sequence number being timed */
151
152 int t_bw_rtttime; /* used for bandwidth calculation */
153 tcp_seq t_bw_rtseq; /* used for bandwidth calculation */
154
155 int t_rxtcur; /* current retransmit value (ticks) */
156 u_int t_maxseg; /* maximum segment size */
157 int t_srtt; /* smoothed round-trip time */
158 int t_rttvar; /* variance in round-trip time */
159
160 int t_rxtshift; /* log(2) of rexmt exp. backoff */
161 u_int t_rttmin; /* minimum rtt allowed */
162 u_int t_rttbest; /* best rtt we've seen */
163 u_long t_rttupdated; /* number of times rtt sampled */
164 u_long max_sndwnd; /* largest window peer has offered */
165
166 int t_softerror; /* possible error not yet reported */
167 /* out-of-band data */
168 char t_oobflags; /* have some */
169 char t_iobc; /* input character */
170 #define TCPOOB_HAVEDATA 0x01
171 #define TCPOOB_HADDATA 0x02
172 /* RFC 1323 variables */
173 u_char snd_scale; /* window scaling for send window */
174 u_char rcv_scale; /* window scaling for recv window */
175 u_char request_r_scale; /* pending window scaling */
176 u_char requested_s_scale;
177 u_long ts_recent; /* timestamp echo data */
178
179 u_long ts_recent_age; /* when last updated */
180 tcp_seq last_ack_sent;
181 /* RFC 1644 variables */
182 tcp_cc cc_send; /* send connection count */
183 tcp_cc cc_recv; /* receive connection count */
184 /* experimental */
185 u_long snd_cwnd_prev; /* cwnd prior to retransmit */
186 u_long snd_ssthresh_prev; /* ssthresh prior to retransmit */
187 tcp_seq snd_recover_prev; /* snd_recover prior to retransmit */
188 u_long t_badrxtwin; /* window for retransmit recovery */
189 u_char snd_limited; /* segments limited transmitted */
190 /* anti DoS counters */
191 u_long rcv_second; /* start of interval second */
192 u_long rcv_pps; /* received packets per second */
193 u_long rcv_byps; /* received bytes per second */
194 /* SACK related state */
195 int sack_enable; /* enable SACK for this connection */
196 int snd_numholes; /* number of holes seen by sender */
197 struct sackhole *snd_holes; /* linked list of holes (sorted) */
198 tcp_seq rcv_lastsack; /* last seq number(+1) sack'd by rcv'r*/
199 int rcv_numsacks; /* # distinct sack blks present */
200 struct sackblk sackblks[MAX_SACK_BLKS]; /* seq nos. of sack blocks */
201 tcp_seq sack_newdata; /* New data xmitted in this recovery
202 episode starts at this seq number */
203 };
204
205 #define IN_FASTRECOVERY(tp) (tp->t_flags & TF_FASTRECOVERY)
206 #define ENTER_FASTRECOVERY(tp) tp->t_flags |= TF_FASTRECOVERY
207 #define EXIT_FASTRECOVERY(tp) tp->t_flags &= ~TF_FASTRECOVERY
208
209 #ifdef TCP_SIGNATURE
210 /*
211 * Defines which are needed by the xform_tcp module and tcp_[in|out]put
212 * for SADB verification and lookup.
213 */
214 #define TCP_SIGLEN 16 /* length of computed digest in bytes */
215 #define TCP_KEYLEN_MIN 1 /* minimum length of TCP-MD5 key */
216 #define TCP_KEYLEN_MAX 80 /* maximum length of TCP-MD5 key */
217 /*
218 * Only a single SA per host may be specified at this time. An SPI is
219 * needed in order for the KEY_ALLOCSA() lookup to work.
220 */
221 #define TCP_SIG_SPI 0x1000
222 #endif /* TCP_SIGNATURE */
223
224 /*
225 * Structure to hold TCP options that are only used during segment
226 * processing (in tcp_input), but not held in the tcpcb.
227 * It's basically used to reduce the number of parameters
228 * to tcp_dooptions.
229 */
230 struct tcpopt {
231 u_long to_flags; /* which options are present */
232 #define TOF_TS 0x0001 /* timestamp */
233 #define TOF_CC 0x0002 /* CC and CCnew are exclusive */
234 #define TOF_CCNEW 0x0004
235 #define TOF_CCECHO 0x0008
236 #define TOF_MSS 0x0010
237 #define TOF_SCALE 0x0020
238 #define TOF_SIGNATURE 0x0040 /* signature option present */
239 #define TOF_SIGLEN 0x0080 /* signature length valid (RFC2385) */
240 #define TOF_SACK 0x0100 /* Peer sent SACK option */
241 u_int32_t to_tsval;
242 u_int32_t to_tsecr;
243 tcp_cc to_cc; /* holds CC or CCnew */
244 tcp_cc to_ccecho;
245 u_int16_t to_mss;
246 u_int8_t to_requested_s_scale;
247 u_int8_t to_pad;
248 };
249
250 #ifdef _NETINET_IN_PCB_H_
251 struct syncache {
252 inp_gen_t sc_inp_gencnt; /* pointer check */
253 struct tcpcb *sc_tp; /* tcb for listening socket */
254 struct mbuf *sc_ipopts; /* source route */
255 struct in_conninfo sc_inc; /* addresses */
256 u_int32_t sc_tsrecent;
257 u_int32_t sc_flowlabel; /* IPv6 flowlabel */
258 tcp_cc sc_cc_send; /* holds CC or CCnew */
259 tcp_cc sc_cc_recv;
260 tcp_seq sc_irs; /* seq from peer */
261 tcp_seq sc_iss; /* our ISS */
262 u_long sc_rxttime; /* retransmit time */
263 u_int16_t sc_rxtslot; /* retransmit counter */
264 u_int16_t sc_peer_mss; /* peer's MSS */
265 u_int16_t sc_wnd; /* advertised window */
266 u_int8_t sc_requested_s_scale:4,
267 sc_request_r_scale:4;
268 u_int8_t sc_flags;
269 #define SCF_NOOPT 0x01 /* no TCP options */
270 #define SCF_WINSCALE 0x02 /* negotiated window scaling */
271 #define SCF_TIMESTAMP 0x04 /* negotiated timestamps */
272 #define SCF_CC 0x08 /* negotiated CC */
273 #define SCF_UNREACH 0x10 /* icmp unreachable received */
274 #define SCF_SIGNATURE 0x20 /* send MD5 digests */
275 #define SCF_SACK 0x80 /* send SACK option */
276 TAILQ_ENTRY(syncache) sc_hash;
277 TAILQ_ENTRY(syncache) sc_timerq;
278 };
279
280 struct syncache_head {
281 TAILQ_HEAD(, syncache) sch_bucket;
282 u_int sch_length;
283 };
284 #else
285 struct in_conninfo;
286 #endif /* _NETINET_IN_PCB_H_ */
287
288 struct hc_metrics_lite { /* must stay in sync with hc_metrics */
289 u_long rmx_mtu; /* MTU for this path */
290 u_long rmx_ssthresh; /* outbound gateway buffer limit */
291 u_long rmx_rtt; /* estimated round trip time */
292 u_long rmx_rttvar; /* estimated rtt variance */
293 u_long rmx_bandwidth; /* estimated bandwidth */
294 u_long rmx_cwnd; /* congestion window */
295 u_long rmx_sendpipe; /* outbound delay-bandwidth product */
296 u_long rmx_recvpipe; /* inbound delay-bandwidth product */
297 };
298
299 struct tcptw {
300 struct inpcb *tw_inpcb; /* XXX back pointer to internet pcb */
301 tcp_seq snd_nxt;
302 tcp_seq rcv_nxt;
303 tcp_seq iss;
304 tcp_seq irs;
305 tcp_cc cc_recv;
306 tcp_cc cc_send;
307 u_short last_win; /* cached window value */
308 u_short tw_so_options; /* copy of so_options */
309 struct ucred *tw_cred; /* user credentials */
310 u_long t_recent;
311 u_long t_starttime;
312 int tw_time;
313 LIST_ENTRY(tcptw) tw_2msl;
314 };
315
316 /*
317 * The TAO cache entry which is stored in the tcp hostcache.
318 */
319 struct rmxp_tao {
320 tcp_cc tao_cc; /* latest CC in valid SYN */
321 tcp_cc tao_ccsent; /* latest CC sent to peer */
322 u_short tao_mssopt; /* peer's cached MSS */
323 #ifdef notyet
324 u_short tao_flags; /* cache status flags */
325 #define TAOF_DONT 0x0001 /* peer doesn't understand rfc1644 */
326 #define TAOF_OK 0x0002 /* peer does understand rfc1644 */
327 #define TAOF_UNDEF 0 /* we don't know yet */
328 #endif /* notyet */
329 };
330
331 #define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb)
332 #define intotw(ip) ((struct tcptw *)(ip)->inp_ppcb)
333 #define sototcpcb(so) (intotcpcb(sotoinpcb(so)))
334
335 /*
336 * The smoothed round-trip time and estimated variance
337 * are stored as fixed point numbers scaled by the values below.
338 * For convenience, these scales are also used in smoothing the average
339 * (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed).
340 * With these scales, srtt has 3 bits to the right of the binary point,
341 * and thus an "ALPHA" of 0.875. rttvar has 2 bits to the right of the
342 * binary point, and is smoothed with an ALPHA of 0.75.
343 */
344 #define TCP_RTT_SCALE 32 /* multiplier for srtt; 3 bits frac. */
345 #define TCP_RTT_SHIFT 5 /* shift for srtt; 3 bits frac. */
346 #define TCP_RTTVAR_SCALE 16 /* multiplier for rttvar; 2 bits */
347 #define TCP_RTTVAR_SHIFT 4 /* shift for rttvar; 2 bits */
348 #define TCP_DELTA_SHIFT 2 /* see tcp_input.c */
349
350 /*
351 * The initial retransmission should happen at rtt + 4 * rttvar.
352 * Because of the way we do the smoothing, srtt and rttvar
353 * will each average +1/2 tick of bias. When we compute
354 * the retransmit timer, we want 1/2 tick of rounding and
355 * 1 extra tick because of +-1/2 tick uncertainty in the
356 * firing of the timer. The bias will give us exactly the
357 * 1.5 tick we need. But, because the bias is
358 * statistical, we have to test that we don't drop below
359 * the minimum feasible timer (which is 2 ticks).
360 * This version of the macro adapted from a paper by Lawrence
361 * Brakmo and Larry Peterson which outlines a problem caused
362 * by insufficient precision in the original implementation,
363 * which results in inappropriately large RTO values for very
364 * fast networks.
365 */
366 #define TCP_REXMTVAL(tp) \
367 max((tp)->t_rttmin, (((tp)->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT)) \
368 + (tp)->t_rttvar) >> TCP_DELTA_SHIFT)
369
370 /*
371 * TCP statistics.
372 * Many of these should be kept per connection,
373 * but that's inconvenient at the moment.
374 */
375 struct tcpstat {
376 u_long tcps_connattempt; /* connections initiated */
377 u_long tcps_accepts; /* connections accepted */
378 u_long tcps_connects; /* connections established */
379 u_long tcps_drops; /* connections dropped */
380 u_long tcps_conndrops; /* embryonic connections dropped */
381 u_long tcps_minmssdrops; /* average minmss too low drops */
382 u_long tcps_closed; /* conn. closed (includes drops) */
383 u_long tcps_segstimed; /* segs where we tried to get rtt */
384 u_long tcps_rttupdated; /* times we succeeded */
385 u_long tcps_delack; /* delayed acks sent */
386 u_long tcps_timeoutdrop; /* conn. dropped in rxmt timeout */
387 u_long tcps_rexmttimeo; /* retransmit timeouts */
388 u_long tcps_persisttimeo; /* persist timeouts */
389 u_long tcps_keeptimeo; /* keepalive timeouts */
390 u_long tcps_keepprobe; /* keepalive probes sent */
391 u_long tcps_keepdrops; /* connections dropped in keepalive */
392
393 u_long tcps_sndtotal; /* total packets sent */
394 u_long tcps_sndpack; /* data packets sent */
395 u_long tcps_sndbyte; /* data bytes sent */
396 u_long tcps_sndrexmitpack; /* data packets retransmitted */
397 u_long tcps_sndrexmitbyte; /* data bytes retransmitted */
398 u_long tcps_sndrexmitbad; /* unnecessary packet retransmissions */
399 u_long tcps_sndacks; /* ack-only packets sent */
400 u_long tcps_sndprobe; /* window probes sent */
401 u_long tcps_sndurg; /* packets sent with URG only */
402 u_long tcps_sndwinup; /* window update-only packets sent */
403 u_long tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */
404
405 u_long tcps_rcvtotal; /* total packets received */
406 u_long tcps_rcvpack; /* packets received in sequence */
407 u_long tcps_rcvbyte; /* bytes received in sequence */
408 u_long tcps_rcvbadsum; /* packets received with ccksum errs */
409 u_long tcps_rcvbadoff; /* packets received with bad offset */
410 u_long tcps_rcvmemdrop; /* packets dropped for lack of memory */
411 u_long tcps_rcvshort; /* packets received too short */
412 u_long tcps_rcvduppack; /* duplicate-only packets received */
413 u_long tcps_rcvdupbyte; /* duplicate-only bytes received */
414 u_long tcps_rcvpartduppack; /* packets with some duplicate data */
415 u_long tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */
416 u_long tcps_rcvoopack; /* out-of-order packets received */
417 u_long tcps_rcvoobyte; /* out-of-order bytes received */
418 u_long tcps_rcvpackafterwin; /* packets with data after window */
419 u_long tcps_rcvbyteafterwin; /* bytes rcvd after window */
420 u_long tcps_rcvafterclose; /* packets rcvd after "close" */
421 u_long tcps_rcvwinprobe; /* rcvd window probe packets */
422 u_long tcps_rcvdupack; /* rcvd duplicate acks */
423 u_long tcps_rcvacktoomuch; /* rcvd acks for unsent data */
424 u_long tcps_rcvackpack; /* rcvd ack packets */
425 u_long tcps_rcvackbyte; /* bytes acked by rcvd acks */
426 u_long tcps_rcvwinupd; /* rcvd window update packets */
427 u_long tcps_pawsdrop; /* segments dropped due to PAWS */
428 u_long tcps_predack; /* times hdr predict ok for acks */
429 u_long tcps_preddat; /* times hdr predict ok for data pkts */
430 u_long tcps_pcbcachemiss;
431 u_long tcps_cachedrtt; /* times cached RTT in route updated */
432 u_long tcps_cachedrttvar; /* times cached rttvar updated */
433 u_long tcps_cachedssthresh; /* times cached ssthresh updated */
434 u_long tcps_usedrtt; /* times RTT initialized from route */
435 u_long tcps_usedrttvar; /* times RTTVAR initialized from rt */
436 u_long tcps_usedssthresh; /* times ssthresh initialized from rt*/
437 u_long tcps_persistdrop; /* timeout in persist state */
438 u_long tcps_badsyn; /* bogus SYN, e.g. premature ACK */
439 u_long tcps_mturesent; /* resends due to MTU discovery */
440 u_long tcps_listendrop; /* listen queue overflows */
441 u_long tcps_badrst; /* ignored RSTs in the window */
442
443 u_long tcps_sc_added; /* entry added to syncache */
444 u_long tcps_sc_retransmitted; /* syncache entry was retransmitted */
445 u_long tcps_sc_dupsyn; /* duplicate SYN packet */
446 u_long tcps_sc_dropped; /* could not reply to packet */
447 u_long tcps_sc_completed; /* successful extraction of entry */
448 u_long tcps_sc_bucketoverflow; /* syncache per-bucket limit hit */
449 u_long tcps_sc_cacheoverflow; /* syncache cache limit hit */
450 u_long tcps_sc_reset; /* RST removed entry from syncache */
451 u_long tcps_sc_stale; /* timed out or listen socket gone */
452 u_long tcps_sc_aborted; /* syncache entry aborted */
453 u_long tcps_sc_badack; /* removed due to bad ACK */
454 u_long tcps_sc_unreach; /* ICMP unreachable received */
455 u_long tcps_sc_zonefail; /* zalloc() failed */
456 u_long tcps_sc_sendcookie; /* SYN cookie sent */
457 u_long tcps_sc_recvcookie; /* SYN cookie received */
458
459 u_long tcps_hc_added; /* entry added to hostcache */
460 u_long tcps_hc_bucketoverflow; /* hostcache per bucket limit hit */
461
462 /* SACK related stats */
463 u_long tcps_sack_recovery_episode; /* SACK recovery episodes */
464 u_long tcps_sack_rexmits; /* SACK rexmit segments */
465 u_long tcps_sack_rexmit_bytes; /* SACK rexmit bytes */
466 u_long tcps_sack_rcv_blocks; /* SACK blocks (options) received */
467 u_long tcps_sack_send_blocks; /* SACK blocks (options) sent */
468 u_long tcps_sack_sboverflow; /* times scoreboard overflowed */
469 };
470
471 /*
472 * TCB structure exported to user-land via sysctl(3).
473 * Evil hack: declare only if in_pcb.h and sys/socketvar.h have been
474 * included. Not all of our clients do.
475 */
476 #if defined(_NETINET_IN_PCB_H_) && defined(_SYS_SOCKETVAR_H_)
477 struct xtcpcb {
478 size_t xt_len;
479 struct inpcb xt_inp;
480 struct tcpcb xt_tp;
481 struct xsocket xt_socket;
482 u_quad_t xt_alignment_hack;
483 };
484 #endif
485
486 /*
487 * Names for TCP sysctl objects
488 */
489 #define TCPCTL_DO_RFC1323 1 /* use RFC-1323 extensions */
490 #define TCPCTL_DO_RFC1644 2 /* use RFC-1644 extensions */
491 #define TCPCTL_MSSDFLT 3 /* MSS default */
492 #define TCPCTL_STATS 4 /* statistics (read-only) */
493 #define TCPCTL_RTTDFLT 5 /* default RTT estimate */
494 #define TCPCTL_KEEPIDLE 6 /* keepalive idle timer */
495 #define TCPCTL_KEEPINTVL 7 /* interval to send keepalives */
496 #define TCPCTL_SENDSPACE 8 /* send buffer space */
497 #define TCPCTL_RECVSPACE 9 /* receive buffer space */
498 #define TCPCTL_KEEPINIT 10 /* timeout for establishing syn */
499 #define TCPCTL_PCBLIST 11 /* list of all outstanding PCBs */
500 #define TCPCTL_DELACKTIME 12 /* time before sending delayed ACK */
501 #define TCPCTL_V6MSSDFLT 13 /* MSS default for IPv6 */
502 #define TCPCTL_SACK 14 /* Selective Acknowledgement,rfc 2018 */
503 #define TCPCTL_DROP 15 /* drop tcp connection */
504 #define TCPCTL_MAXID 16
505
506 #define TCPCTL_NAMES { \
507 { 0, 0 }, \
508 { "rfc1323", CTLTYPE_INT }, \
509 { "rfc1644", CTLTYPE_INT }, \
510 { "mssdflt", CTLTYPE_INT }, \
511 { "stats", CTLTYPE_STRUCT }, \
512 { "rttdflt", CTLTYPE_INT }, \
513 { "keepidle", CTLTYPE_INT }, \
514 { "keepintvl", CTLTYPE_INT }, \
515 { "sendspace", CTLTYPE_INT }, \
516 { "recvspace", CTLTYPE_INT }, \
517 { "keepinit", CTLTYPE_INT }, \
518 { "pcblist", CTLTYPE_STRUCT }, \
519 { "delacktime", CTLTYPE_INT }, \
520 { "v6mssdflt", CTLTYPE_INT }, \
521 { "maxid", CTLTYPE_INT }, \
522 }
523
524
525 #ifdef _KERNEL
526 #ifdef SYSCTL_DECL
527 SYSCTL_DECL(_net_inet_tcp);
528 SYSCTL_DECL(_net_inet_tcp_sack);
529 #endif
530
531 extern struct inpcbhead tcb; /* head of queue of active tcpcb's */
532 extern struct inpcbinfo tcbinfo;
533 extern struct tcpstat tcpstat; /* tcp statistics */
534 extern int tcp_mssdflt; /* XXX */
535 extern int tcp_minmss;
536 extern int tcp_minmssoverload;
537 extern int tcp_delack_enabled;
538 extern int tcp_do_newreno;
539 extern int path_mtu_discovery;
540 extern int ss_fltsz;
541 extern int ss_fltsz_local;
542
543 extern int tcp_do_sack; /* SACK enabled/disabled */
544
545 struct tcpcb *
546 tcp_close(struct tcpcb *);
547 void tcp_twstart(struct tcpcb *);
548 int tcp_twrecycleable(struct tcptw *tw);
549 struct tcptw *
550 tcp_twclose(struct tcptw *_tw, int _reuse);
551 void tcp_ctlinput(int, struct sockaddr *, void *);
552 int tcp_ctloutput(struct socket *, struct sockopt *);
553 struct tcpcb *
554 tcp_drop(struct tcpcb *, int);
555 void tcp_drain(void);
556 void tcp_fasttimo(void);
557 void tcp_init(void);
558 void tcp_fini(void *);
559 void tcp_reass_init(void);
560 void tcp_input(struct mbuf *, int);
561 u_long tcp_maxmtu(struct in_conninfo *);
562 u_long tcp_maxmtu6(struct in_conninfo *);
563 void tcp_mss(struct tcpcb *, int);
564 int tcp_mssopt(struct in_conninfo *);
565 struct inpcb *
566 tcp_drop_syn_sent(struct inpcb *, int);
567 struct inpcb *
568 tcp_mtudisc(struct inpcb *, int);
569 struct tcpcb *
570 tcp_newtcpcb(struct inpcb *);
571 int tcp_output(struct tcpcb *);
572 void tcp_respond(struct tcpcb *, void *,
573 struct tcphdr *, struct mbuf *, tcp_seq, tcp_seq, int);
574 int tcp_twrespond(struct tcptw *, int);
575 void tcp_setpersist(struct tcpcb *);
576 #ifdef TCP_SIGNATURE
577 int tcp_signature_compute(struct mbuf *, int, int, int, u_char *, u_int);
578 #endif
579 void tcp_slowtimo(void);
580 struct tcptemp *
581 tcpip_maketemplate(struct inpcb *);
582 void tcpip_fillheaders(struct inpcb *, void *, void *);
583 struct tcpcb *
584 tcp_timers(struct tcpcb *, int);
585 void tcp_trace(int, int, struct tcpcb *, void *, struct tcphdr *, int);
586 void tcp_xmit_bandwidth_limit(struct tcpcb *tp, tcp_seq ack_seq);
587 void syncache_init(void);
588 void syncache_unreach(struct in_conninfo *, struct tcphdr *);
589 int syncache_expand(struct in_conninfo *, struct tcphdr *,
590 struct socket **, struct mbuf *);
591 int syncache_add(struct in_conninfo *, struct tcpopt *,
592 struct tcphdr *, struct socket **, struct mbuf *);
593 void syncache_chkrst(struct in_conninfo *, struct tcphdr *);
594 void syncache_badack(struct in_conninfo *);
595 /*
596 * All tcp_hc_* functions are IPv4 and IPv6 (via in_conninfo)
597 */
598 void tcp_hc_init(void);
599 void tcp_hc_get(struct in_conninfo *, struct hc_metrics_lite *);
600 u_long tcp_hc_getmtu(struct in_conninfo *);
601 void tcp_hc_gettao(struct in_conninfo *, struct rmxp_tao *);
602 void tcp_hc_updatemtu(struct in_conninfo *, u_long);
603 void tcp_hc_update(struct in_conninfo *, struct hc_metrics_lite *);
604 void tcp_hc_updatetao(struct in_conninfo *, int, tcp_cc, u_short);
605 /* update which tao field */
606 #define TCP_HC_TAO_CC 0x1
607 #define TCP_HC_TAO_CCSENT 0x2
608 #define TCP_HC_TAO_MSSOPT 0x3
609
610 extern struct pr_usrreqs tcp_usrreqs;
611 extern u_long tcp_sendspace;
612 extern u_long tcp_recvspace;
613 tcp_seq tcp_new_isn(struct tcpcb *);
614
615 int tcp_sack_option(struct tcpcb *,struct tcphdr *,u_char *,int);
616 void tcp_update_sack_list(struct tcpcb *tp, tcp_seq rcv_laststart, tcp_seq rcv_lastend);
617 void tcp_del_sackholes(struct tcpcb *, struct tcphdr *);
618 void tcp_clean_sackreport(struct tcpcb *tp);
619 void tcp_sack_adjust(struct tcpcb *tp);
620 struct sackhole *tcp_sack_output(struct tcpcb *tp, int *sack_bytes_rexmt);
621 int tcp_sacked_bytes(struct tcpcb *tp, int *lost_not_rexmitted);
622 void tcp_sack_partialack(struct tcpcb *, struct tcphdr *);
623 void tcp_free_sackholes(struct tcpcb *tp);
624 int tcp_newreno(struct tcpcb *, struct tcphdr *);
625 u_long tcp_seq_subtract(u_long, u_long );
626 #ifdef TCP_SACK_DEBUG
627 void tcp_print_holes(struct tcpcb *tp);
628 #endif /* TCP_SACK_DEBUG */
629
630 #endif /* _KERNEL */
631
632 #endif /* _NETINET_TCP_VAR_H_ */
Cache object: dc1a8713af8b883e3f41e7ccfba512b7
|