1/*
2 * Copyright (c) 2000-2017 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
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27 */
28/*
29 * Copyright (c) 1982, 1986, 1993, 1994, 1995
30 * The Regents of the University of California. All rights reserved.
31 *
32 * Redistribution and use in source and binary forms, with or without
33 * modification, are permitted provided that the following conditions
34 * are met:
35 * 1. Redistributions of source code must retain the above copyright
36 * notice, this list of conditions and the following disclaimer.
37 * 2. Redistributions in binary form must reproduce the above copyright
38 * notice, this list of conditions and the following disclaimer in the
39 * documentation and/or other materials provided with the distribution.
40 * 3. All advertising materials mentioning features or use of this software
41 * must display the following acknowledgement:
42 * This product includes software developed by the University of
43 * California, Berkeley and its contributors.
44 * 4. Neither the name of the University nor the names of its contributors
45 * may be used to endorse or promote products derived from this software
46 * without specific prior written permission.
47 *
48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58 * SUCH DAMAGE.
59 *
60 * @(#)tcp_var.h 8.4 (Berkeley) 5/24/95
61 * $FreeBSD: src/sys/netinet/tcp_var.h,v 1.56.2.8 2001/08/22 00:59:13 silby Exp $
62 */
63
64#ifndef _NETINET_TCP_VAR_H_
65#define _NETINET_TCP_VAR_H_
66#include <sys/types.h>
67#include <sys/appleapiopts.h>
68#include <sys/queue.h>
69#include <netinet/in_pcb.h>
70#include <netinet/tcp.h>
71#include <netinet/tcp_timer.h>
72
73#if defined(__LP64__)
74#define _TCPCB_PTR(x) u_int32_t
75#define _TCPCB_LIST_HEAD(name, type) \
76struct name { \
77 u_int32_t lh_first; \
78}
79#else
80#define _TCPCB_PTR(x) x
81#define _TCPCB_LIST_HEAD(name, type) LIST_HEAD(name, type)
82#endif
83
84#ifdef KERNEL_PRIVATE
85
86#define TCP_RETRANSHZ 1000 /* granularity of TCP timestamps, 1ms */
87/* Minimum time quantum within which the timers are coalesced */
88#define TCP_TIMER_10MS_QUANTUM (TCP_RETRANSHZ/100) /* every 10ms */
89#define TCP_TIMER_100MS_QUANTUM (TCP_RETRANSHZ/10) /* every 100ms */
90#define TCP_TIMER_500MS_QUANTUM (TCP_RETRANSHZ/2) /* every 500ms */
91
92#define TCP_RETRANSHZ_TO_USEC 1000
93
94#define N_TIME_WAIT_SLOTS 128 /* must be power of 2 */
95
96/* Always allow at least 16 packets worth of recv window when adjusting
97 * recv window using inter-packet arrival jitter.
98 */
99#define MIN_IAJ_WIN 16
100
101/* A variation in delay of this many milliseconds is tolerable. This limit has to
102 * be low but greater than zero. We also use standard deviation on jitter to adjust
103 * this limit for different link and connection types.
104 */
105#define ALLOWED_IAJ 5
106
107/* Ignore the first few packets on a connection until the ACK clock gets going
108 */
109#define IAJ_IGNORE_PKTCNT 40
110
111/* Let the accumulated IAJ value increase by this threshold at most. This limit
112 * will control how many ALLOWED_IAJ measurements a receiver will have to see
113 * before opening the receive window
114 */
115#define ACC_IAJ_HIGH_THRESH 100
116
117/* When accumulated IAJ reaches this value, the receiver starts to react by
118 * closing the window
119 */
120#define ACC_IAJ_REACT_LIMIT 200
121
122/* If the number of small packets (smaller than IAJ packet size) seen on a
123 * connection is more than this threshold, reset the size and learn it again.
124 * This is needed because the sender might send smaller segments after PMTU
125 * discovery and the receiver has to learn the new size.
126 */
127#define RESET_IAJ_SIZE_THRESH 20
128
129/*
130 * Adaptive timeout is a read/write timeout specified by the application to
131 * get a socket event when the transport layer detects a stall in data
132 * transfer. The value specified is the number of probes that can be sent
133 * to the peer before generating an event. Since it is not specified as
134 * a time value, the timeout will adjust based on the RTT seen on the link.
135 * The timeout will start only when there is an indication that the read/write
136 * operation is not making progress.
137 *
138 * If a write operation stalls, the probe will be retransmission of data.
139 * If a read operation stalls, the probe will be a keep-alive packet.
140 *
141 * The maximum value of adaptive timeout is set to 10 which will allow
142 * transmission of enough number of probes to the peer.
143 */
144#define TCP_ADAPTIVE_TIMEOUT_MAX 10
145
146#define TCP_CONNECTIVITY_PROBES_MAX 5
147
148/*
149 * Kernel variables for tcp.
150 */
151
152/* TCP segment queue entry */
153struct tseg_qent {
154 LIST_ENTRY(tseg_qent) tqe_q;
155 int tqe_len; /* TCP segment data length */
156 struct tcphdr *tqe_th; /* a pointer to tcp header */
157 struct mbuf *tqe_m; /* mbuf contains packet */
158};
159LIST_HEAD(tsegqe_head, tseg_qent);
160
161struct sackblk {
162 tcp_seq start; /* start seq no. of sack block */
163 tcp_seq end; /* end seq no. */
164};
165
166struct sackhole {
167 tcp_seq start; /* start seq no. of hole */
168 tcp_seq end; /* end seq no. */
169 tcp_seq rxmit; /* next seq. no in hole to be retransmitted */
170 u_int32_t rxmit_start; /* timestamp of first retransmission */
171 TAILQ_ENTRY(sackhole) scblink; /* scoreboard linkage */
172};
173
174struct sackhint {
175 struct sackhole *nexthole;
176 int sack_bytes_rexmit;
177};
178
179struct tcp_rxt_seg {
180 tcp_seq rx_start;
181 tcp_seq rx_end;
182 u_int16_t rx_count;
183 u_int16_t rx_flags;
184#define TCP_RXT_SPURIOUS 0x1 /* received DSACK notification */
185#define TCP_RXT_DSACK_FOR_TLP 0x2
186 SLIST_ENTRY(tcp_rxt_seg) rx_link;
187};
188
189struct tcp_notify_ack_marker {
190 tcp_seq notify_snd_una; /* Notify when snd_una crosses this seq */
191 tcp_notify_ack_id_t notify_id;
192 SLIST_ENTRY(tcp_notify_ack_marker) notify_next;
193};
194
195struct tcptemp {
196 u_char tt_ipgen[40]; /* the size must be of max ip header, now IPv6 */
197 struct tcphdr tt_t;
198};
199
200struct bwmeas {
201 tcp_seq bw_start; /* start of bw measurement */
202 uint32_t bw_ts; /* timestamp when bw measurement started */
203 uint32_t bw_size; /* burst size in bytes for this bw measurement */
204 uint32_t bw_minsizepkts; /* Min burst size as segments */
205 uint32_t bw_maxsizepkts; /* Max burst size as segments */
206 uint32_t bw_minsize; /* Min size in bytes */
207 uint32_t bw_maxsize; /* Max size in bytes */
208 uint32_t bw_sndbw; /* Measured send bandwidth */
209 uint32_t bw_sndbw_max; /* Max measured bandwidth */
210 uint32_t bw_rcvbw_max; /* Max receive bandwidth measured */
211};
212
213/* MPTCP Data sequence map entry */
214struct mpt_dsn_map {
215 uint64_t mpt_dsn; /* data seq num recvd */
216 uint32_t mpt_sseq; /* relative subflow # */
217 uint16_t mpt_len; /* length of mapping */
218 uint16_t mpt_csum; /* checksum value if on */
219 uint8_t mpt_dfin; /* It's a DATA_FIN */
220};
221#define tcp6cb tcpcb /* for KAME src sync over BSD*'s */
222
223struct tcp_ccstate {
224 union {
225 struct tcp_cubic_state {
226 u_int32_t tc_last_max; /* cwnd at last loss */
227 u_int32_t tc_epoch_start; /* TS of last loss */
228 u_int32_t tc_origin_point; /* window at the start of an epoch */
229 u_int32_t tc_tcp_win; /* computed tcp win */
230 u_int32_t tc_tcp_bytes_acked; /* bytes acked */
231 u_int32_t tc_target_win; /* cubic target win */
232 u_int32_t tc_avg_lastmax; /* Average of last max */
233 u_int32_t tc_mean_deviation; /* Mean absolute deviation */
234 float tc_epoch_period; /* K parameter */
235 } _cubic_state_;
236#define cub_last_max __u__._cubic_state_.tc_last_max
237#define cub_epoch_start __u__._cubic_state_.tc_epoch_start
238#define cub_origin_point __u__._cubic_state_.tc_origin_point
239#define cub_tcp_win __u__._cubic_state_.tc_tcp_win
240#define cub_tcp_bytes_acked __u__._cubic_state_.tc_tcp_bytes_acked
241#define cub_epoch_period __u__._cubic_state_.tc_epoch_period
242#define cub_target_win __u__._cubic_state_.tc_target_win
243#define cub_avg_lastmax __u__._cubic_state_.tc_avg_lastmax
244#define cub_mean_dev __u__._cubic_state_.tc_mean_deviation
245 } __u__;
246};
247
248/*
249 * Tcp control block, one per tcp; fields:
250 * Organized for 16 byte cacheline efficiency.
251 */
252struct tcpcb {
253 struct tsegqe_head t_segq;
254 int t_dupacks; /* consecutive dup acks recd */
255 int t_state; /* state of this connection */
256 uint32_t t_timer[TCPT_NTIMERS]; /* tcp timers */
257 struct tcptimerentry tentry; /* entry in timer list */
258
259 struct inpcb *t_inpcb; /* back pointer to internet pcb */
260 uint32_t t_flags;
261#define TF_ACKNOW 0x00001 /* ack peer immediately */
262#define TF_DELACK 0x00002 /* ack, but try to delay it */
263#define TF_NODELAY 0x00004 /* don't delay packets to coalesce */
264#define TF_NOOPT 0x00008 /* don't use tcp options */
265#define TF_SENTFIN 0x00010 /* have sent FIN */
266#define TF_REQ_SCALE 0x00020 /* have/will request window scaling */
267#define TF_RCVD_SCALE 0x00040 /* other side has requested scaling */
268#define TF_REQ_TSTMP 0x00080 /* have/will request timestamps */
269#define TF_RCVD_TSTMP 0x00100 /* a timestamp was received in SYN */
270#define TF_SACK_PERMIT 0x00200 /* other side said I could SACK */
271#define TF_NEEDSYN 0x00400 /* send SYN (implicit state) */
272#define TF_NEEDFIN 0x00800 /* send FIN (implicit state) */
273#define TF_NOPUSH 0x01000 /* don't push */
274#define TF_REQ_CC 0x02000 /* have/will request CC */
275#define TF_RCVD_CC 0x04000 /* a CC was received in SYN */
276#define TF_SENDCCNEW 0x08000 /* Unused */
277#define TF_MORETOCOME 0x10000 /* More data to be appended to sock */
278#define TF_LOCAL 0x20000 /* connection to a host on local link */
279#define TF_RXWIN0SENT 0x40000 /* sent a receiver win 0 in response */
280#define TF_SLOWLINK 0x80000 /* route is a on a modem speed link */
281#define TF_LASTIDLE 0x100000 /* connection was previously idle */
282#define TF_FASTRECOVERY 0x200000 /* in NewReno Fast Recovery */
283#define TF_WASFRECOVERY 0x400000 /* was in NewReno Fast Recovery */
284#define TF_SIGNATURE 0x800000 /* require MD5 digests (RFC2385) */
285#define TF_MAXSEGSNT 0x1000000 /* last segment sent was a full segment */
286#define TF_STREAMING_ON 0x2000000 /* Receiver detected streaming */
287#define TF_PMTUD 0x4000000 /* Perform Path MTU Discovery for this connection */
288#define TF_CLOSING 0x8000000 /* pending tcp close */
289#define TF_TSO 0x10000000 /* TCP Segment Offloading is enable on this connection */
290#define TF_BLACKHOLE 0x20000000 /* Path MTU Discovery Black Hole detection */
291#define TF_TIMER_ONLIST 0x40000000 /* pcb is on tcp_timer_list */
292#define TF_STRETCHACK 0x80000000 /* receiver is going to delay acks */
293
294 tcp_seq snd_una; /* send unacknowledged */
295 tcp_seq snd_max; /* highest sequence number sent;
296 * used to recognize retransmits
297 */
298 tcp_seq snd_nxt; /* send next */
299 tcp_seq snd_up; /* send urgent pointer */
300
301 tcp_seq snd_wl1; /* window update seg seq number */
302 tcp_seq snd_wl2; /* window update seg ack number */
303 tcp_seq iss; /* initial send sequence number */
304 tcp_seq irs; /* initial receive sequence number */
305
306 tcp_seq rcv_nxt; /* receive next */
307 tcp_seq rcv_adv; /* advertised window */
308 u_int32_t rcv_wnd; /* receive window */
309 tcp_seq rcv_up; /* receive urgent pointer */
310
311 u_int32_t snd_wnd; /* send window */
312 u_int32_t snd_cwnd; /* congestion-controlled window */
313 u_int32_t snd_ssthresh; /* snd_cwnd size threshold for
314 * for slow start exponential to
315 * linear switch
316 */
317 tcp_seq snd_recover; /* for use in NewReno Fast Recovery */
318
319 u_int32_t t_maxopd; /* mss plus options */
320 u_int32_t t_rcvtime; /* time at which a packet was received */
321 u_int32_t t_sndtime; /* time at which we last sent new data */
322 u_int32_t t_starttime; /* time connection was established */
323 int t_rtttime; /* tcp clock when rtt calculation was started */
324 tcp_seq t_rtseq; /* sequence number being timed */
325
326 u_int32_t rfbuf_ts; /* recv buffer autoscaling timestamp */
327 u_int32_t rfbuf_cnt; /* recv buffer autoscaling byte count */
328
329 int t_rxtcur; /* current retransmit value (ticks) */
330 u_int t_maxseg; /* maximum segment size */
331 int t_srtt; /* smoothed round-trip time */
332 int t_rttvar; /* variance in round-trip time */
333
334 u_int64_t t_accsleep_ms; /* accumulated sleep time since last boot */
335 u_int16_t t_reassqlen; /* length of reassembly queue */
336 u_int16_t t_rxtshift; /* log(2) of rexmt exp. backoff */
337 u_int32_t t_rttmin; /* minimum rtt allowed */
338 u_int32_t t_rttbest; /* best rtt we've seen */
339 u_int32_t t_rttcur; /* most recent value of rtt */
340 u_int32_t t_rttupdated; /* number of times rtt sampled */
341 u_int32_t t_rxt_conndroptime; /* retxmt conn gets dropped after this time, when set */
342 u_int32_t t_rxtstart; /* time at which retransmission started */
343 u_int32_t max_sndwnd; /* largest window peer has offered */
344
345 int t_softerror; /* possible error not yet reported */
346/* out-of-band data */
347 char t_oobflags; /* have some */
348 char t_iobc; /* input character */
349#define TCPOOB_HAVEDATA 0x01
350#define TCPOOB_HADDATA 0x02
351/* RFC 1323 variables */
352 u_int8_t snd_scale; /* window scaling for send window */
353 u_int8_t rcv_scale; /* window scaling for recv window */
354 u_int8_t request_r_scale; /* pending window scaling */
355 u_int8_t requested_s_scale;
356 u_int8_t tcp_cc_index; /* index of congestion control algorithm */
357 u_int8_t t_adaptive_rtimo; /* Read timeout used as a multiple of RTT */
358 u_int8_t t_adaptive_wtimo; /* Write timeout used as a multiple of RTT */
359 u_int8_t t_stretchack_delayed; /* stretch ack delayed */
360
361/* State for limiting early retransmits when SACK is not enabled */
362 u_int16_t t_early_rexmt_count; /* count of early rexmts */
363 u_int32_t t_early_rexmt_win; /* window for limiting early rexmts */
364
365 u_int32_t ts_recent; /* timestamp echo data */
366
367 u_int32_t ts_recent_age; /* when last updated */
368 tcp_seq last_ack_sent;
369/* RFC 3465 variables */
370 u_int32_t t_bytes_acked; /* ABC "bytes_acked" parameter */
371
372 int t_lastchain; /* amount of packets chained last time around */
373 u_int16_t t_unacksegs; /* received but unacked segments for delaying acks */
374 u_int8_t t_rexmtthresh; /* duplicate ack threshold for entering fast recovery */
375 u_int8_t t_rtimo_probes; /* number of adaptive rtimo probes sent */
376 u_int32_t t_persist_timeout; /* ZWP persistence limit as set by PERSIST_TIMEOUT */
377 u_int32_t t_persist_stop; /* persistence limit deadline if triggered by ZWP */
378 u_int32_t t_notsent_lowat; /* Low water for not sent data */
379
380/* Receiver state for stretch-ack algorithm */
381 u_int32_t rcv_unackwin; /* to measure win for stretching acks */
382 u_int32_t rcv_by_unackwin; /* bytes seen during the last ack-stretching win */
383 u_int32_t rcv_nostrack_ts; /* timestamp when stretch ack was disabled automatically */
384 u_int32_t rcv_nostrack_pkts; /* pkts received since strech ack was disabled */
385 u_int16_t rcv_waitforss; /* wait for packets during slow-start */
386
387/* ECN stats */
388 u_int16_t ecn_flags;
389#define TE_SETUPSENT 0x0001 /* Indicate we have sent ECN-SETUP SYN or SYN-ACK */
390#define TE_SETUPRECEIVED 0x0002 /* Indicate we have received ECN-SETUP SYN or SYN-ACK */
391#define TE_SENDIPECT 0x0004 /* Indicate we haven't sent or received non-ECN-setup SYN or SYN-ACK */
392#define TE_SENDCWR 0x0008 /* Indicate that the next non-retransmit should have the TCP CWR flag set */
393#define TE_SENDECE 0x0010 /* Indicate that the next packet should have the TCP ECE flag set */
394#define TE_INRECOVERY 0x0020 /* connection entered recovery after receiving ECE */
395#define TE_RECV_ECN_CE 0x0040 /* Received IPTOS_ECN_CE marking atleast once */
396#define TE_RECV_ECN_ECE 0x0080 /* Received ECE marking atleast once */
397#define TE_LOST_SYN 0x0100 /* Lost SYN with ECN setup */
398#define TE_LOST_SYNACK 0x0200 /* Lost SYN-ACK with ECN setup */
399#define TE_ECN_MODE_ENABLE 0x0400 /* Option ECN mode set to enable */
400#define TE_ECN_MODE_DISABLE 0x0800 /* Option ECN mode set to disable */
401#define TE_ENABLE_ECN 0x1000 /* Enable negotiation of ECN */
402#define TE_ECN_ON (TE_SETUPSENT | TE_SETUPRECEIVED) /* Indicate ECN was successfully negotiated on a connection) */
403#define TE_CEHEURI_SET 0x2000 /* We did our CE-probing at the beginning */
404#define TE_CLIENT_SETUP 0x4000 /* setup from client side */
405#define TE_RCVD_SYN_RST 0x8000 /* Received RST to the first ECN enabled SYN */
406
407 u_int32_t t_ecn_recv_ce; /* Received CE from the network */
408 u_int32_t t_ecn_recv_cwr; /* Packets received with CWR */
409
410/* state for bad retransmit recovery */
411 u_int32_t snd_cwnd_prev; /* cwnd prior to retransmit */
412 u_int32_t snd_ssthresh_prev; /* ssthresh prior to retransmit */
413 tcp_seq snd_recover_prev; /* snd_recover prior to retransmit */
414 int t_srtt_prev; /* srtt prior to retransmit */
415 int t_rttvar_prev; /* rttvar prior to retransmit */
416 u_int32_t t_badrexmt_time; /* bad rexmt detection time */
417
418/* Packet reordering metric */
419 u_int16_t t_reorderwin; /* Reordering late time offset */
420
421/* SACK related state */
422 int16_t snd_numholes; /* number of holes seen by sender */
423 tcp_seq sack_newdata; /* New data xmitted in this recovery
424 episode starts at this seq number */
425 TAILQ_HEAD(sackhole_head, sackhole) snd_holes;
426 /* SACK scoreboard (sorted) */
427 tcp_seq snd_fack; /* last seq number(+1) sack'd by rcv'r*/
428 int rcv_numsacks; /* # distinct sack blks present */
429 struct sackblk sackblks[MAX_SACK_BLKS]; /* seq nos. of sack blocks */
430 struct sackhint sackhint; /* SACK scoreboard hint */
431
432 struct mbuf *t_pktlist_head; /* First packet in transmit chain */
433 struct mbuf *t_pktlist_tail; /* Last packet in transmit chain */
434 u_int32_t t_pktlist_sentlen; /* total bytes in transmit chain */
435
436 u_int32_t t_keepidle; /* keepalive idle timer (override global if > 0) */
437 u_int32_t t_keepinit; /* connection timeout, i.e. idle time
438 in SYN_SENT or SYN_RECV state */
439 u_int32_t t_keepintvl; /* interval between keepalives */
440 u_int32_t t_keepcnt; /* number of keepalives before close */
441
442 u_int32_t tso_max_segment_size; /* TSO maximum segment unit for NIC */
443 u_int16_t t_pmtud_lastseg_size; /* size of the last sent segment */
444 u_int16_t t_pmtud_saved_maxopd; /* MSS saved before performing PMTU-D BlackHole detection */
445 u_int32_t t_pmtud_start_ts; /* Time of PMTUD blackhole detection */
446
447 struct
448 {
449 u_int32_t rxduplicatebytes;
450 u_int32_t rxoutoforderbytes;
451 u_int32_t txretransmitbytes;
452 u_int8_t synrxtshift;
453 u_int8_t unused;
454 u_int16_t unused_pad_to_8;
455 u_int32_t rxmitpkts;
456 } t_stat;
457 u_int8_t t_notify_ack_count;
458 u_int8_t t_ecn_recv_ce_pkt; /* Received packet with CE-bit set (independent from last_ack_sent) */
459 u_int16_t t_cached_maxopd; /* default for MSS adjustment using link status report */
460
461 uint32_t bg_ssthresh; /* Slow start threshold until delay increases */
462 uint32_t t_flagsext; /* Another field to accommodate more flags */
463#define TF_RXTFINDROP 0x1 /* Drop conn after retransmitting FIN 3 times */
464#define TF_RCVUNACK_WAITSS 0x2 /* set when the receiver should not stretch acks */
465#define TF_BWMEAS_INPROGRESS 0x4 /* Indicate BW meas is happening */
466#define TF_MEASURESNDBW 0x8 /* Measure send bw on this connection */
467#define TF_LRO_OFFLOADED 0x10 /* Connection LRO offloaded */
468#define TF_SACK_ENABLE 0x20 /* SACK is enabled */
469#define TF_RECOMPUTE_RTT 0x40 /* recompute RTT after spurious retransmit */
470#define TF_DETECT_READSTALL 0x80 /* Used to detect a stall during read operation */
471#define TF_RECV_THROTTLE 0x100 /* Input throttling active */
472#define TF_NOSTRETCHACK 0x200 /* ack every other packet */
473#define TF_NOTIMEWAIT 0x800 /* Avoid going into time-wait */
474#define TF_SENT_TLPROBE 0x1000 /* Sent data in PTO */
475#define TF_PKTS_REORDERED 0x2000 /* Detected reordering */
476#define TF_DELAY_RECOVERY 0x4000 /* delay fast recovery */
477#define TF_FORCE 0x8000 /* force 1 byte out */
478#define TF_DISABLE_STRETCHACK 0x10000 /* auto-disable stretch ack */
479#define TF_NOBLACKHOLE_DETECTION 0x20000 /* Disable PMTU blackhole detection */
480#define TF_DISABLE_DSACK 0x40000 /* Ignore DSACK due to n/w duplication */
481#define TF_RESCUE_RXT 0x80000 /* SACK rescue retransmit */
482#define TF_CWND_NONVALIDATED 0x100000 /* cwnd non validated */
483#define TF_PROBING 0x200000 /* Trigger probe timeout */
484#define TF_FASTOPEN 0x400000 /* TCP Fastopen is enabled */
485#define TF_REASS_INPROG 0x800000 /* Reassembly is in progress */
486#define TF_FASTOPEN_HEUR 0x1000000 /* Make sure that heuristics get never skipped */
487
488#if TRAFFIC_MGT
489 /* Inter-arrival jitter related state */
490 uint32_t iaj_rcv_ts; /* tcp clock when the first packet was received */
491 uint16_t iaj_size; /* Size of packet for iaj measurement */
492 uint8_t iaj_small_pkt; /* Count of packets smaller than iaj_size */
493 uint8_t t_pipeack_ind; /* index for next pipeack sample */
494 uint16_t iaj_pktcnt; /* packet count, to avoid throttling initially */
495 uint16_t acc_iaj; /* Accumulated iaj */
496 uint32_t avg_iaj; /* Mean */
497 uint32_t std_dev_iaj; /* Standard deviation */
498#endif /* TRAFFIC_MGT */
499 struct bwmeas *t_bwmeas; /* State for bandwidth measurement */
500 uint32_t t_lropktlen; /* Bytes in a LRO frame */
501 tcp_seq t_idleat; /* rcv_nxt at idle time */
502 TAILQ_ENTRY(tcpcb) t_twentry; /* link for time wait queue */
503 struct tcp_ccstate *t_ccstate; /* congestion control related state */
504/* Tail loss probe related state */
505 tcp_seq t_tlphighrxt; /* snd_nxt after PTO */
506 u_int32_t t_tlpstart; /* timestamp at PTO */
507/* DSACK data receiver state */
508 tcp_seq t_dsack_lseq; /* DSACK left sequence */
509 tcp_seq t_dsack_rseq; /* DSACK right sequence */
510/* DSACK data sender state */
511 SLIST_HEAD(tcp_rxt_seghead, tcp_rxt_seg) t_rxt_segments;
512 tcp_seq t_dsack_lastuna; /* snd_una when last recovery episode started */
513/* state for congestion window validation (draft-ietf-tcpm-newcwv-07) */
514#define TCP_PIPEACK_SAMPLE_COUNT 3
515 u_int32_t t_pipeack_sample[TCP_PIPEACK_SAMPLE_COUNT]; /* pipeack, bytes acked within RTT */
516 tcp_seq t_pipeack_lastuna; /* una when pipeack measurement started */
517 u_int32_t t_pipeack;
518 u_int32_t t_lossflightsize;
519
520#if MPTCP
521 u_int32_t t_mpflags; /* flags for multipath TCP */
522
523#define TMPF_PREESTABLISHED 0x00000001 /* conn in pre-established state */
524#define TMPF_SND_KEYS 0x00000002 /* indicates that keys should be send */
525#define TMPF_MPTCP_TRUE 0x00000004 /* negotiated MPTCP successfully */
526#define TMPF_MPTCP_RCVD_KEY 0x00000008 /* state for 3-way handshake */
527#define TMPF_SND_MPPRIO 0x00000010 /* send priority of subflow */
528#define TMPF_SND_REM_ADDR 0x00000020 /* initiate address removal */
529#define TMPF_RCVD_DACK 0x00000040 /* received a data-ack */
530#define TMPF_JOINED_FLOW 0x00000080 /* Indicates additional flow */
531#define TMPF_BACKUP_PATH 0x00000100 /* Indicates backup path */
532#define TMPF_MPTCP_ACKNOW 0x00000200 /* Send Data ACK */
533#define TMPF_SEND_DSN 0x00000400 /* Send DSN mapping */
534#define TMPF_SEND_DFIN 0x00000800 /* Send Data FIN */
535#define TMPF_RECV_DFIN 0x00001000 /* Recv Data FIN */
536#define TMPF_SENT_JOIN 0x00002000 /* Sent Join */
537#define TMPF_RECVD_JOIN 0x00004000 /* Received Join */
538#define TMPF_RESET 0x00008000 /* Send RST */
539#define TMPF_TCP_FALLBACK 0x00010000 /* Fallback to TCP */
540#define TMPF_FASTCLOSERCV 0x00020000 /* Received Fastclose option */
541#define TMPF_EMBED_DSN 0x00040000 /* tp has DSN mapping */
542#define TMPF_MPTCP_READY 0x00080000 /* Can send DSS options on data */
543#define TMPF_INFIN_SENT 0x00100000 /* Sent infinite mapping */
544#define TMPF_SND_MPFAIL 0x00200000 /* Received mapping csum failure */
545#define TMPF_SND_JACK 0x00400000 /* Send a Join-ACK */
546#define TMPF_TFO_REQUEST 0x00800000 /* TFO Requested */
547
548#define TMPF_MPTCP_SIGNALS (TMPF_SND_MPPRIO | TMPF_SND_REM_ADDR | TMPF_SND_MPFAIL | TMPF_SND_KEYS | TMPF_SND_JACK)
549
550 tcp_seq t_mpuna; /* unacknowledged sequence */
551 struct mptcb *t_mptcb; /* pointer to MPTCP TCB */
552 struct mptsub *t_mpsub; /* pointer to the MPTCP subflow */
553 struct mpt_dsn_map t_rcv_map; /* Receive mapping list */
554 u_int8_t t_local_aid; /* Addr Id for authentication */
555 u_int8_t t_rem_aid; /* Addr ID of another subflow */
556 u_int8_t t_mprxtshift; /* join retransmission */
557#endif /* MPTCP */
558
559#define TFO_F_OFFER_COOKIE 0x01 /* We will offer a cookie */
560#define TFO_F_COOKIE_VALID 0x02 /* The received cookie is valid */
561#define TFO_F_COOKIE_REQ 0x04 /* Client requested a new cookie */
562#define TFO_F_COOKIE_SENT 0x08 /* Client did send a cookie in the SYN */
563#define TFO_F_SYN_LOSS 0x10 /* A SYN-loss triggered a fallback to regular TCP on the client-side */
564#define TFO_F_NO_SNDPROBING 0x20 /* This network is guaranteed to support TFO in the upstream direction */
565#define TFO_F_HEURISTIC_DONE 0x40 /* We have already marked this network as bad */
566 u_int8_t t_tfo_flags;
567#define TFO_S_SYNDATA_RCV 0x01 /* SYN+data has been received */
568#define TFO_S_COOKIEREQ_RECV 0x02 /* TFO-cookie request received */
569#define TFO_S_COOKIE_SENT 0x04 /* TFO-cookie announced in SYN/ACK */
570#define TFO_S_COOKIE_INVALID 0x08 /* Received TFO-cookie is invalid */
571#define TFO_S_COOKIE_REQ 0x10 /* TFO-cookie requested within the SYN */
572#define TFO_S_COOKIE_RCV 0x20 /* TFO-cookie received in SYN/ACK */
573#define TFO_S_SYN_DATA_SENT 0x40 /* SYN+data sent */
574#define TFO_S_SYN_DATA_ACKED 0x80 /* SYN+data has been acknowledged in SYN/ACK */
575#define TFO_S_SYN_LOSS 0x0100 /* SYN+TFO has been lost - fallback to regular TCP */
576#define TFO_S_COOKIE_WRONG 0x0200 /* Cookie we sent in the SYN was wrong */
577#define TFO_S_NO_COOKIE_RCV 0x0400 /* We asked for a cookie but didn't get one */
578#define TFO_S_HEURISTICS_DISABLE 0x0800 /* TFO-heuristics disabled it for this connection */
579#define TFO_S_SEND_BLACKHOLE 0x1000 /* TFO got blackholed in the send direction */
580#define TFO_S_RECV_BLACKHOLE 0x2000 /* TFO got blackholed in the recv direction */
581#define TFO_S_ONE_BYTE_PROXY 0x4000 /* TFO failed because of a proxy acknowledging just one byte */
582 u_int16_t t_tfo_stats;
583
584 u_int8_t t_tfo_probes; /* TFO-probes we did send */
585/*
586 * This here is the TFO-probing state-machine. Transitions are as follows:
587 *
588 * Current state: PROBE_NONE
589 * Event: SYN+DATA acknowledged
590 * Action: Transition to PROBE_PROBING and set keepalive-timer
591 *
592 * Current state: PROBE_PROBING (initial state)
593 * Event: Receive data
594 * Action: Transition to PROBE_NONE and cancel keepalive-timer
595 * Event: Receive ACK that does not indicate a hole
596 * Action: Transition to PROBE_NONE and cancel keepalive-timer
597 * Event: Receive ACK that indicates a hole
598 * Action: Transition to PROBE_WAIT_DATA and set a short timer
599 * to wait for the final segment.
600 * Event: Keepalive-timeout (did not receive any segment)
601 * Action: Signal ETIMEDOUT as with regular keepalive-timers
602 *
603 * Current state: PROBE_WAIT_DATA
604 * Event: Receive data
605 * Action: Transition to PROBE_NONE and cancel keepalive-timer
606 * Event: Data-timeout (did not receive the expected data)
607 * Action: Signal ENODATA up to the app and close everything.
608 */
609#define TFO_PROBE_NONE 0 /* Not probing now */
610#define TFO_PROBE_PROBING 1 /* Sending out TCP-keepalives waiting for reply */
611#define TFO_PROBE_WAIT_DATA 2 /* Received reply, waiting for data */
612 u_int8_t t_tfo_probe_state;
613
614 u_int32_t t_rcvoopack; /* out-of-order packets received */
615 u_int32_t t_pawsdrop; /* segments dropped due to PAWS */
616 u_int32_t t_sack_recovery_episode; /* SACK recovery episodes */
617 u_int32_t t_reordered_pkts; /* packets reorderd */
618 u_int32_t t_dsack_sent; /* Sent DSACK notification */
619 u_int32_t t_dsack_recvd; /* Received a valid DSACK option */
620 SLIST_HEAD(,tcp_notify_ack_marker) t_notify_ack; /* state for notifying data acknowledgements */
621 u_int32_t t_recv_throttle_ts; /* TS for start of recv throttle */
622 u_int32_t t_rxt_minimum_timeout; /* minimum retransmit timeout in ms */
623 uint32_t t_challengeack_last; /* last time challenge ACK was sent per sec */
624 uint32_t t_challengeack_count; /* # of challenge ACKs already sent per sec */
625};
626
627#define IN_FASTRECOVERY(tp) (tp->t_flags & TF_FASTRECOVERY)
628#define SACK_ENABLED(tp) (tp->t_flagsext & TF_SACK_ENABLE)
629
630/*
631 * If the connection is in a throttled state due to advisory feedback from
632 * the interface output queue, reset that state. We do this in favor
633 * of entering recovery because the data transfer during recovery
634 * should be just a trickle and it will help to improve performance.
635 * We also do not want to back off twice in the same RTT.
636 */
637#define ENTER_FASTRECOVERY(_tp_) do { \
638 (_tp_)->t_flags |= TF_FASTRECOVERY; \
639 if (INP_IS_FLOW_CONTROLLED((_tp_)->t_inpcb)) \
640 inp_reset_fc_state((_tp_)->t_inpcb); \
641 if (!SLIST_EMPTY(&tp->t_rxt_segments)) \
642 tcp_rxtseg_clean(tp); \
643} while(0)
644
645#define EXIT_FASTRECOVERY(_tp_) do { \
646 (_tp_)->t_flags &= ~TF_FASTRECOVERY; \
647 (_tp_)->t_dupacks = 0; \
648 (_tp_)->t_rexmtthresh = tcprexmtthresh; \
649 (_tp_)->t_bytes_acked = 0; \
650 (_tp_)->ecn_flags &= ~TE_INRECOVERY; \
651 (_tp_)->t_timer[TCPT_PTO] = 0; \
652 (_tp_)->t_flagsext &= ~TF_RESCUE_RXT; \
653 (_tp_)->t_lossflightsize = 0; \
654} while(0)
655
656/*
657 * When the number of duplicate acks received is less than
658 * the retransmit threshold, use Limited Transmit algorithm
659 */
660extern int tcprexmtthresh;
661#define ALLOW_LIMITED_TRANSMIT(_tp_) \
662 ((_tp_)->t_dupacks > 0 && \
663 (_tp_)->t_dupacks < (_tp_)->t_rexmtthresh && \
664 ((_tp_)->t_flagsext & (TF_PKTS_REORDERED|TF_DELAY_RECOVERY)) \
665 != (TF_PKTS_REORDERED|TF_DELAY_RECOVERY))
666
667/*
668 * This condition is true is timestamp option is supported
669 * on a connection.
670 */
671#define TSTMP_SUPPORTED(_tp_) \
672 (((_tp_)->t_flags & (TF_REQ_TSTMP|TF_RCVD_TSTMP)) == \
673 (TF_REQ_TSTMP|TF_RCVD_TSTMP))
674
675/*
676 * This condition is true if window scale option is supported
677 * on a connection
678 */
679#define TCP_WINDOW_SCALE_ENABLED(_tp_) \
680 (((_tp_)->t_flags & (TF_RCVD_SCALE|TF_REQ_SCALE)) == \
681 (TF_RCVD_SCALE|TF_REQ_SCALE))
682
683/* Is ECN enabled end-to-end */
684#define TCP_ECN_ENABLED(_tp_) \
685 (((_tp_)->ecn_flags & (TE_ECN_ON)) == (TE_ECN_ON))
686
687/*
688 * Gives number of bytes acked by this ack
689 */
690#define BYTES_ACKED(_th_, _tp_) \
691 ((_th_)->th_ack - (_tp_)->snd_una)
692
693/* Returns true if a DSACK option should be sent */
694#define TCP_SEND_DSACK_OPT(_tp_) \
695 ((_tp_)->t_dsack_lseq > 0 && (_tp_)->t_dsack_rseq > 0)
696
697/* Check if DSACK option should be processed */
698#define TCP_DSACK_ENABLED(tp) (tcp_dsack_enable == 1 && \
699 !(tp->t_flagsext & TF_DISABLE_DSACK))
700
701/*
702 * Returns true if a DSACK sequence is within the max send window that will
703 * be accepted. In order to set a window to validate sequence numbers, the
704 * max send window within which a DSACK option is processed is limited.
705 *
706 * We need to choose a maximum window to check if the sequence number is
707 * within the window. One arbitrary choice is 256 * MSS because if the
708 * window is as large as 256 segments it might be big enough to ignore the
709 * DSACK option. Choosing a much larger limit means that the memory for
710 * retransmit segments can be held for a longer time.
711 */
712#define TCP_DSACK_MAX_SEND_WINDOW(_tp_) ((_tp_)->t_maxseg << 8)
713#define TCP_DSACK_SEQ_IN_WINDOW(_tp_, _seq_, _una_) \
714 (SEQ_LEQ((_seq_), (_tp_)->snd_max) && \
715 SEQ_GEQ((_seq_), ((_una_) - TCP_DSACK_MAX_SEND_WINDOW(_tp_))))
716
717#define TCP_RESET_REXMT_STATE(_tp_) do { \
718 (_tp_)->t_rxtshift = 0; \
719 (_tp_)->t_rxtstart = 0; \
720 mptcp_reset_rexmit_state((_tp_)); \
721} while(0);
722
723#define TCP_AUTORCVBUF_MAX(_ifp_) (((_ifp_) != NULL && (IFNET_IS_CELLULAR((_ifp_))) && ((_ifp_)->if_eflags & IFEF_3CA)) ? \
724 (tcp_autorcvbuf_max << 1) : tcp_autorcvbuf_max)
725
726enum tcp_cc_event {
727 TCP_CC_CWND_INIT, /* 0 */
728 TCP_CC_INSEQ_ACK_RCVD, /* 1 */
729 TCP_CC_ACK_RCVD, /* 2 */
730 TCP_CC_ENTER_FASTRECOVERY, /* 3 */
731 TCP_CC_IN_FASTRECOVERY, /* 4 */
732 TCP_CC_EXIT_FASTRECOVERY, /* 5 */
733 TCP_CC_PARTIAL_ACK, /* 6 */
734 TCP_CC_IDLE_TIMEOUT, /* 7 */
735 TCP_CC_REXMT_TIMEOUT, /* 8 */
736 TCP_CC_ECN_RCVD, /* 9 */
737 TCP_CC_BAD_REXMT_RECOVERY, /* 10 */
738 TCP_CC_OUTPUT_ERROR, /* 11 */
739 TCP_CC_CHANGE_ALGO, /* 12 */
740 TCP_CC_FLOW_CONTROL, /* 13 */
741 TCP_CC_SUSPEND, /* 14 */
742 TCP_CC_LIMITED_TRANSMIT, /* 15 */
743 TCP_CC_EARLY_RETRANSMIT, /* 16 */
744 TCP_CC_TLP_RECOVERY, /* 17 */
745 TCP_CC_TLP_RECOVER_LASTPACKET, /* 18 */
746 TCP_CC_DELAY_FASTRECOVERY, /* 19 */
747 TCP_CC_TLP_IN_FASTRECOVERY, /* 20 */
748 TCP_CC_DSACK_BAD_REXMT /* 21 */
749};
750
751/*
752 * Structure to hold TCP options that are only used during segment
753 * processing (in tcp_input), but not held in the tcpcb.
754 * It's basically used to reduce the number of parameters
755 * to tcp_dooptions.
756 */
757struct tcpopt {
758 u_int32_t to_flags; /* which options are present */
759#define TOF_TS 0x0001 /* timestamp */
760#define TOF_MSS 0x0010
761#define TOF_SCALE 0x0020
762#define TOF_SIGNATURE 0x0040 /* signature option present */
763#define TOF_SIGLEN 0x0080 /* signature length valid (RFC2385) */
764#define TOF_SACK 0x0100 /* Peer sent SACK option */
765#define TOF_MPTCP 0x0200 /* MPTCP options to be dropped */
766#define TOF_TFO 0x0400 /* TFO cookie option present */
767#define TOF_TFOREQ 0x0800 /* TFO cookie request present */
768 u_int32_t to_tsval;
769 u_int32_t to_tsecr;
770 u_int16_t to_mss;
771 u_int8_t to_requested_s_scale;
772 u_int8_t to_nsacks; /* number of SACK blocks */
773 u_char *to_sacks; /* pointer to the first SACK blocks */
774 u_char *to_tfo; /* pointer to the TFO cookie */
775};
776
777/*
778 * The TAO cache entry which is stored in the protocol family specific
779 * portion of the route metrics.
780 */
781struct rmxp_tao {
782 tcp_cc tao_cc; /* latest CC in valid SYN */
783 tcp_cc tao_ccsent; /* latest CC sent to peer */
784 u_short tao_mssopt; /* peer's cached MSS */
785#ifdef notyet
786 u_short tao_flags; /* cache status flags */
787#define TAOF_DONT 0x0001 /* peer doesn't understand rfc1644 */
788#define TAOF_OK 0x0002 /* peer does understand rfc1644 */
789#define TAOF_UNDEF 0 /* we don't know yet */
790#endif /* notyet */
791};
792#define rmx_taop(r) ((struct rmxp_tao *)(r).rmx_filler)
793
794#define intotcpcb(ip) ((struct tcpcb *)(ip)->inp_ppcb)
795#define sototcpcb(so) (intotcpcb(sotoinpcb(so)))
796
797/* TFO-specific defines */
798#define TFO_COOKIE_LEN_MIN 4
799#define TFO_COOKIE_LEN_DEFAULT 8
800#define TFO_COOKIE_LEN_MAX 16
801
802/*
803 * The initial retransmission should happen at rtt + 4 * rttvar.
804 * Because of the way we do the smoothing, srtt and rttvar
805 * will each average +1/2 tick of bias. When we compute
806 * the retransmit timer, we want 1/2 tick of rounding and
807 * 1 extra tick because of +-1/2 tick uncertainty in the
808 * firing of the timer. The bias will give us exactly the
809 * 1.5 tick we need. But, because the bias is
810 * statistical, we have to test that we don't drop below
811 * the minimum feasible timer (which is 2 ticks).
812 * This version of the macro adapted from a paper by Lawrence
813 * Brakmo and Larry Peterson which outlines a problem caused
814 * by insufficient precision in the original implementation,
815 * which results in inappropriately large RTO values for very
816 * fast networks.
817 */
818#define TCP_REXMTVAL(tp) \
819 max((tp)->t_rttmin, (((tp)->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT)) \
820 + (tp)->t_rttvar) >> TCP_DELTA_SHIFT)
821
822/*
823 * Jaguar compatible TCP control block, for xtcpcb
824 * Does not have the old fields
825 */
826struct otcpcb {
827#else
828struct tseg_qent;
829_TCPCB_LIST_HEAD(tsegqe_head, tseg_qent);
830
831struct tcpcb {
832#endif /* KERNEL_PRIVATE */
833#if defined(KERNEL_PRIVATE)
834 u_int32_t t_segq;
835#else
836 struct tsegqe_head t_segq;
837#endif /* KERNEL_PRIVATE */
838 int t_dupacks; /* consecutive dup acks recd */
839 u_int32_t unused; /* unused now: was t_template */
840
841 int t_timer[TCPT_NTIMERS_EXT]; /* tcp timers */
842
843 _TCPCB_PTR(struct inpcb *) t_inpcb; /* back pointer to internet pcb */
844 int t_state; /* state of this connection */
845 u_int t_flags;
846#define TF_ACKNOW 0x00001 /* ack peer immediately */
847#define TF_DELACK 0x00002 /* ack, but try to delay it */
848#define TF_NODELAY 0x00004 /* don't delay packets to coalesce */
849#define TF_NOOPT 0x00008 /* don't use tcp options */
850#define TF_SENTFIN 0x00010 /* have sent FIN */
851#define TF_REQ_SCALE 0x00020 /* have/will request window scaling */
852#define TF_RCVD_SCALE 0x00040 /* other side has requested scaling */
853#define TF_REQ_TSTMP 0x00080 /* have/will request timestamps */
854#define TF_RCVD_TSTMP 0x00100 /* a timestamp was received in SYN */
855#define TF_SACK_PERMIT 0x00200 /* other side said I could SACK */
856#define TF_NEEDSYN 0x00400 /* send SYN (implicit state) */
857#define TF_NEEDFIN 0x00800 /* send FIN (implicit state) */
858#define TF_NOPUSH 0x01000 /* don't push */
859#define TF_REQ_CC 0x02000 /* have/will request CC */
860#define TF_RCVD_CC 0x04000 /* a CC was received in SYN */
861#define TF_SENDCCNEW 0x08000 /* Not implemented */
862#define TF_MORETOCOME 0x10000 /* More data to be appended to sock */
863#define TF_LQ_OVERFLOW 0x20000 /* listen queue overflow */
864#define TF_RXWIN0SENT 0x40000 /* sent a receiver win 0 in response */
865#define TF_SLOWLINK 0x80000 /* route is a on a modem speed link */
866
867 int t_force; /* 1 if forcing out a byte */
868
869 tcp_seq snd_una; /* send unacknowledged */
870 tcp_seq snd_max; /* highest sequence number sent;
871 * used to recognize retransmits
872 */
873 tcp_seq snd_nxt; /* send next */
874 tcp_seq snd_up; /* send urgent pointer */
875
876 tcp_seq snd_wl1; /* window update seg seq number */
877 tcp_seq snd_wl2; /* window update seg ack number */
878 tcp_seq iss; /* initial send sequence number */
879 tcp_seq irs; /* initial receive sequence number */
880
881 tcp_seq rcv_nxt; /* receive next */
882 tcp_seq rcv_adv; /* advertised window */
883 u_int32_t rcv_wnd; /* receive window */
884 tcp_seq rcv_up; /* receive urgent pointer */
885
886 u_int32_t snd_wnd; /* send window */
887 u_int32_t snd_cwnd; /* congestion-controlled window */
888 u_int32_t snd_ssthresh; /* snd_cwnd size threshold for
889 * for slow start exponential to
890 * linear switch
891 */
892 u_int t_maxopd; /* mss plus options */
893
894 u_int32_t t_rcvtime; /* time at which a packet was received */
895 u_int32_t t_starttime; /* time connection was established */
896 int t_rtttime; /* round trip time */
897 tcp_seq t_rtseq; /* sequence number being timed */
898
899 int t_rxtcur; /* current retransmit value (ticks) */
900 u_int t_maxseg; /* maximum segment size */
901 int t_srtt; /* smoothed round-trip time */
902 int t_rttvar; /* variance in round-trip time */
903
904 int t_rxtshift; /* log(2) of rexmt exp. backoff */
905 u_int t_rttmin; /* minimum rtt allowed */
906 u_int32_t t_rttupdated; /* number of times rtt sampled */
907 u_int32_t max_sndwnd; /* largest window peer has offered */
908
909 int t_softerror; /* possible error not yet reported */
910/* out-of-band data */
911 char t_oobflags; /* have some */
912 char t_iobc; /* input character */
913#define TCPOOB_HAVEDATA 0x01
914#define TCPOOB_HADDATA 0x02
915/* RFC 1323 variables */
916 u_char snd_scale; /* window scaling for send window */
917 u_char rcv_scale; /* window scaling for recv window */
918 u_char request_r_scale; /* pending window scaling */
919 u_char requested_s_scale;
920 u_int32_t ts_recent; /* timestamp echo data */
921
922 u_int32_t ts_recent_age; /* when last updated */
923 tcp_seq last_ack_sent;
924/* RFC 1644 variables */
925 tcp_cc cc_send; /* send connection count */
926 tcp_cc cc_recv; /* receive connection count */
927 tcp_seq snd_recover; /* for use in fast recovery */
928/* experimental */
929 u_int32_t snd_cwnd_prev; /* cwnd prior to retransmit */
930 u_int32_t snd_ssthresh_prev; /* ssthresh prior to retransmit */
931 u_int32_t t_badrxtwin; /* window for retransmit recovery */
932};
933
934#define tcps_ecn_setup tcps_ecn_client_success
935#define tcps_sent_cwr tcps_ecn_recv_ece
936#define tcps_sent_ece tcps_ecn_sent_ece
937
938/*
939 * TCP statistics.
940 * Many of these should be kept per connection,
941 * but that's inconvenient at the moment.
942 */
943struct tcpstat {
944 u_int32_t tcps_connattempt; /* connections initiated */
945 u_int32_t tcps_accepts; /* connections accepted */
946 u_int32_t tcps_connects; /* connections established */
947 u_int32_t tcps_drops; /* connections dropped */
948 u_int32_t tcps_conndrops; /* embryonic connections dropped */
949 u_int32_t tcps_closed; /* conn. closed (includes drops) */
950 u_int32_t tcps_segstimed; /* segs where we tried to get rtt */
951 u_int32_t tcps_rttupdated; /* times we succeeded */
952 u_int32_t tcps_delack; /* delayed acks sent */
953 u_int32_t tcps_timeoutdrop; /* conn. dropped in rxmt timeout */
954 u_int32_t tcps_rexmttimeo; /* retransmit timeouts */
955 u_int32_t tcps_persisttimeo; /* persist timeouts */
956 u_int32_t tcps_keeptimeo; /* keepalive timeouts */
957 u_int32_t tcps_keepprobe; /* keepalive probes sent */
958 u_int32_t tcps_keepdrops; /* connections dropped in keepalive */
959
960 u_int32_t tcps_sndtotal; /* total packets sent */
961 u_int32_t tcps_sndpack; /* data packets sent */
962 u_int32_t tcps_sndbyte; /* data bytes sent */
963 u_int32_t tcps_sndrexmitpack; /* data packets retransmitted */
964 u_int32_t tcps_sndrexmitbyte; /* data bytes retransmitted */
965 u_int32_t tcps_sndacks; /* ack-only packets sent */
966 u_int32_t tcps_sndprobe; /* window probes sent */
967 u_int32_t tcps_sndurg; /* packets sent with URG only */
968 u_int32_t tcps_sndwinup; /* window update-only packets sent */
969 u_int32_t tcps_sndctrl; /* control (SYN|FIN|RST) packets sent */
970
971 u_int32_t tcps_rcvtotal; /* total packets received */
972 u_int32_t tcps_rcvpack; /* packets received in sequence */
973 u_int32_t tcps_rcvbyte; /* bytes received in sequence */
974 u_int32_t tcps_rcvbadsum; /* packets received with ccksum errs */
975 u_int32_t tcps_rcvbadoff; /* packets received with bad offset */
976 u_int32_t tcps_rcvmemdrop; /* packets dropped for lack of memory */
977 u_int32_t tcps_rcvshort; /* packets received too short */
978 u_int32_t tcps_rcvduppack; /* duplicate-only packets received */
979 u_int32_t tcps_rcvdupbyte; /* duplicate-only bytes received */
980 u_int32_t tcps_rcvpartduppack; /* packets with some duplicate data */
981 u_int32_t tcps_rcvpartdupbyte; /* dup. bytes in part-dup. packets */
982 u_int32_t tcps_rcvoopack; /* out-of-order packets received */
983 u_int32_t tcps_rcvoobyte; /* out-of-order bytes received */
984 u_int32_t tcps_rcvpackafterwin; /* packets with data after window */
985 u_int32_t tcps_rcvbyteafterwin; /* bytes rcvd after window */
986 u_int32_t tcps_rcvafterclose; /* packets rcvd after "close" */
987 u_int32_t tcps_rcvwinprobe; /* rcvd window probe packets */
988 u_int32_t tcps_rcvdupack; /* rcvd duplicate acks */
989 u_int32_t tcps_rcvacktoomuch; /* rcvd acks for unsent data */
990 u_int32_t tcps_rcvackpack; /* rcvd ack packets */
991 u_int32_t tcps_rcvackbyte; /* bytes acked by rcvd acks */
992 u_int32_t tcps_rcvwinupd; /* rcvd window update packets */
993 u_int32_t tcps_pawsdrop; /* segments dropped due to PAWS */
994 u_int32_t tcps_predack; /* times hdr predict ok for acks */
995 u_int32_t tcps_preddat; /* times hdr predict ok for data pkts */
996 u_int32_t tcps_pcbcachemiss;
997 u_int32_t tcps_cachedrtt; /* times cached RTT in route updated */
998 u_int32_t tcps_cachedrttvar; /* times cached rttvar updated */
999 u_int32_t tcps_cachedssthresh; /* times cached ssthresh updated */
1000 u_int32_t tcps_usedrtt; /* times RTT initialized from route */
1001 u_int32_t tcps_usedrttvar; /* times RTTVAR initialized from rt */
1002 u_int32_t tcps_usedssthresh; /* times ssthresh initialized from rt*/
1003 u_int32_t tcps_persistdrop; /* timeout in persist state */
1004 u_int32_t tcps_badsyn; /* bogus SYN, e.g. premature ACK */
1005 u_int32_t tcps_mturesent; /* resends due to MTU discovery */
1006 u_int32_t tcps_listendrop; /* listen queue overflows */
1007 u_int32_t tcps_synchallenge; /* challenge ACK due to bad SYN */
1008 u_int32_t tcps_rstchallenge; /* challenge ACK due to bad RST */
1009
1010 /* new stats from FreeBSD 5.4 sync up */
1011 u_int32_t tcps_minmssdrops; /* average minmss too low drops */
1012
1013 u_int32_t tcps_sndrexmitbad; /* unnecessary packet retransmissions */
1014 u_int32_t tcps_badrst; /* ignored RSTs in the window */
1015
1016 u_int32_t tcps_sc_added; /* entry added to syncache */
1017 u_int32_t tcps_sc_retransmitted; /* syncache entry was retransmitted */
1018 u_int32_t tcps_sc_dupsyn; /* duplicate SYN packet */
1019 u_int32_t tcps_sc_dropped; /* could not reply to packet */
1020 u_int32_t tcps_sc_completed; /* successful extraction of entry */
1021 u_int32_t tcps_sc_bucketoverflow; /* syncache per-bucket limit hit */
1022 u_int32_t tcps_sc_cacheoverflow; /* syncache cache limit hit */
1023 u_int32_t tcps_sc_reset; /* RST removed entry from syncache */
1024 u_int32_t tcps_sc_stale; /* timed out or listen socket gone */
1025 u_int32_t tcps_sc_aborted; /* syncache entry aborted */
1026 u_int32_t tcps_sc_badack; /* removed due to bad ACK */
1027 u_int32_t tcps_sc_unreach; /* ICMP unreachable received */
1028 u_int32_t tcps_sc_zonefail; /* zalloc() failed */
1029 u_int32_t tcps_sc_sendcookie; /* SYN cookie sent */
1030 u_int32_t tcps_sc_recvcookie; /* SYN cookie received */
1031
1032 u_int32_t tcps_hc_added; /* entry added to hostcache */
1033 u_int32_t tcps_hc_bucketoverflow; /* hostcache per bucket limit hit */
1034
1035 /* SACK related stats */
1036 u_int32_t tcps_sack_recovery_episode; /* SACK recovery episodes */
1037 u_int32_t tcps_sack_rexmits; /* SACK rexmit segments */
1038 u_int32_t tcps_sack_rexmit_bytes; /* SACK rexmit bytes */
1039 u_int32_t tcps_sack_rcv_blocks; /* SACK blocks (options) received */
1040 u_int32_t tcps_sack_send_blocks; /* SACK blocks (options) sent */
1041 u_int32_t tcps_sack_sboverflow; /* SACK sendblock overflow */
1042
1043 u_int32_t tcps_bg_rcvtotal; /* total background packets received */
1044 u_int32_t tcps_rxtfindrop; /* drop conn after retransmitting FIN */
1045 u_int32_t tcps_fcholdpacket; /* packets withheld because of flow control */
1046
1047 /* LRO related stats */
1048 u_int32_t tcps_coalesced_pack; /* number of coalesced packets */
1049 u_int32_t tcps_flowtbl_full; /* times flow table was full */
1050 u_int32_t tcps_flowtbl_collision; /* collisions in flow tbl */
1051 u_int32_t tcps_lro_twopack; /* 2 packets coalesced */
1052 u_int32_t tcps_lro_multpack; /* 3 or 4 pkts coalesced */
1053 u_int32_t tcps_lro_largepack; /* 5 or more pkts coalesced */
1054
1055 u_int32_t tcps_limited_txt; /* Limited transmit used */
1056 u_int32_t tcps_early_rexmt; /* Early retransmit used */
1057 u_int32_t tcps_sack_ackadv; /* Cumulative ack advanced along with sack */
1058
1059 /* Checksum related stats */
1060 u_int32_t tcps_rcv_swcsum; /* tcp swcksum (inbound), packets */
1061 u_int32_t tcps_rcv_swcsum_bytes; /* tcp swcksum (inbound), bytes */
1062 u_int32_t tcps_rcv6_swcsum; /* tcp6 swcksum (inbound), packets */
1063 u_int32_t tcps_rcv6_swcsum_bytes; /* tcp6 swcksum (inbound), bytes */
1064 u_int32_t tcps_snd_swcsum; /* tcp swcksum (outbound), packets */
1065 u_int32_t tcps_snd_swcsum_bytes; /* tcp swcksum (outbound), bytes */
1066 u_int32_t tcps_snd6_swcsum; /* tcp6 swcksum (outbound), packets */
1067 u_int32_t tcps_snd6_swcsum_bytes; /* tcp6 swcksum (outbound), bytes */
1068 u_int32_t tcps_msg_unopkts; /* unordered packet on TCP msg stream */
1069 u_int32_t tcps_msg_unoappendfail; /* failed to append unordered pkt */
1070 u_int32_t tcps_msg_sndwaithipri; /* send is waiting for high priority data */
1071
1072 /* MPTCP Related stats */
1073 u_int32_t tcps_invalid_mpcap; /* Invalid MPTCP capable opts */
1074 u_int32_t tcps_invalid_joins; /* Invalid MPTCP joins */
1075 u_int32_t tcps_mpcap_fallback; /* TCP fallback in primary */
1076 u_int32_t tcps_join_fallback; /* No MPTCP in secondary */
1077 u_int32_t tcps_estab_fallback; /* DSS option dropped */
1078 u_int32_t tcps_invalid_opt; /* Catchall error stat */
1079 u_int32_t tcps_mp_outofwin; /* Packet lies outside the
1080 shared recv window */
1081 u_int32_t tcps_mp_reducedwin; /* Reduced subflow window */
1082 u_int32_t tcps_mp_badcsum; /* Bad DSS csum */
1083 u_int32_t tcps_mp_oodata; /* Out of order data */
1084 u_int32_t tcps_mp_switches; /* number of subflow switch */
1085 u_int32_t tcps_mp_rcvtotal; /* number of rcvd packets */
1086 u_int32_t tcps_mp_rcvbytes; /* number of bytes received */
1087 u_int32_t tcps_mp_sndpacks; /* number of data packs sent */
1088 u_int32_t tcps_mp_sndbytes; /* number of bytes sent */
1089 u_int32_t tcps_join_rxmts; /* join ack retransmits */
1090 u_int32_t tcps_tailloss_rto; /* RTO due to tail loss */
1091 u_int32_t tcps_reordered_pkts; /* packets reorderd */
1092 u_int32_t tcps_recovered_pkts; /* recovered after loss */
1093 u_int32_t tcps_pto; /* probe timeout */
1094 u_int32_t tcps_rto_after_pto; /* RTO after a probe */
1095 u_int32_t tcps_tlp_recovery; /* TLP induced fast recovery */
1096 u_int32_t tcps_tlp_recoverlastpkt; /* TLP recoverd last pkt */
1097 u_int32_t tcps_ecn_client_success; /* client-side connection negotiated ECN */
1098 u_int32_t tcps_ecn_recv_ece; /* ECE received, sent CWR */
1099 u_int32_t tcps_ecn_sent_ece; /* Sent ECE notification */
1100 u_int32_t tcps_detect_reordering; /* Detect pkt reordering */
1101 u_int32_t tcps_delay_recovery; /* Delay fast recovery */
1102 u_int32_t tcps_avoid_rxmt; /* Retransmission was avoided */
1103 u_int32_t tcps_unnecessary_rxmt; /* Retransmission was not needed */
1104 u_int32_t tcps_nostretchack; /* disabled stretch ack algorithm on a connection */
1105 u_int32_t tcps_rescue_rxmt; /* SACK rescue retransmit */
1106 u_int32_t tcps_pto_in_recovery; /* rescue retransmit in fast recovery */
1107 u_int32_t tcps_pmtudbh_reverted; /* PMTU Blackhole detection, segment size reverted */
1108
1109 /* DSACK related statistics */
1110 u_int32_t tcps_dsack_disable; /* DSACK disabled due to n/w duplication */
1111 u_int32_t tcps_dsack_ackloss; /* ignore DSACK due to ack loss */
1112 u_int32_t tcps_dsack_badrexmt; /* DSACK based bad rexmt recovery */
1113 u_int32_t tcps_dsack_sent; /* Sent DSACK notification */
1114 u_int32_t tcps_dsack_recvd; /* Received a valid DSACK option */
1115 u_int32_t tcps_dsack_recvd_old; /* Received an out of window DSACK option */
1116
1117 /* MPTCP Subflow selection stats */
1118 u_int32_t tcps_mp_sel_symtomsd; /* By symptomsd */
1119 u_int32_t tcps_mp_sel_rtt; /* By RTT comparison */
1120 u_int32_t tcps_mp_sel_rto; /* By RTO comparison */
1121 u_int32_t tcps_mp_sel_peer; /* By peer's output pattern */
1122 u_int32_t tcps_mp_num_probes; /* Number of probes sent */
1123 u_int32_t tcps_mp_verdowngrade; /* MPTCP version downgrade */
1124 u_int32_t tcps_drop_after_sleep; /* drop after long AP sleep */
1125 u_int32_t tcps_probe_if; /* probe packets after interface availability */
1126 u_int32_t tcps_probe_if_conflict; /* Can't send probe packets for interface */
1127
1128 u_int32_t tcps_ecn_client_setup; /* Attempted ECN setup from client side */
1129 u_int32_t tcps_ecn_server_setup; /* Attempted ECN setup from server side */
1130 u_int32_t tcps_ecn_server_success; /* server-side connection negotiated ECN */
1131 u_int32_t tcps_ecn_lost_synack; /* Lost SYN-ACK with ECN setup */
1132 u_int32_t tcps_ecn_lost_syn; /* Lost SYN with ECN setup */
1133 u_int32_t tcps_ecn_not_supported; /* Server did not support ECN setup */
1134 u_int32_t tcps_ecn_recv_ce; /* Received CE from the network */
1135 u_int32_t tcps_ecn_conn_recv_ce; /* Number of connections received CE atleast once */
1136 u_int32_t tcps_ecn_conn_recv_ece; /* Number of connections received ECE atleast once */
1137 u_int32_t tcps_ecn_conn_plnoce; /* Number of connections that received no CE and sufferred packet loss */
1138 u_int32_t tcps_ecn_conn_pl_ce; /* Number of connections that received CE and sufferred packet loss */
1139 u_int32_t tcps_ecn_conn_nopl_ce; /* Number of connections that received CE and sufferred no packet loss */
1140 u_int32_t tcps_ecn_fallback_synloss; /* Number of times we did fall back due to SYN-Loss */
1141 u_int32_t tcps_ecn_fallback_reorder; /* Number of times we fallback because we detected the PAWS-issue */
1142 u_int32_t tcps_ecn_fallback_ce; /* Number of times we fallback because we received too many CEs */
1143
1144 /* TFO-related statistics */
1145 u_int32_t tcps_tfo_syn_data_rcv; /* Received a SYN+data with valid cookie */
1146 u_int32_t tcps_tfo_cookie_req_rcv;/* Received a TFO cookie-request */
1147 u_int32_t tcps_tfo_cookie_sent; /* Offered a TFO-cookie to the client */
1148 u_int32_t tcps_tfo_cookie_invalid;/* Received an invalid TFO-cookie */
1149 u_int32_t tcps_tfo_cookie_req; /* Cookie requested with the SYN */
1150 u_int32_t tcps_tfo_cookie_rcv; /* Cookie received in a SYN/ACK */
1151 u_int32_t tcps_tfo_syn_data_sent; /* SYN+data+cookie sent */
1152 u_int32_t tcps_tfo_syn_data_acked;/* SYN+data has been acknowledged */
1153 u_int32_t tcps_tfo_syn_loss; /* SYN+TFO has been lost and we fallback */
1154 u_int32_t tcps_tfo_blackhole; /* TFO got blackholed by a middlebox. */
1155 u_int32_t tcps_tfo_cookie_wrong; /* TFO-cookie we sent was wrong */
1156 u_int32_t tcps_tfo_no_cookie_rcv; /* We asked for a cookie but didn't get one */
1157 u_int32_t tcps_tfo_heuristics_disable; /* TFO got disabled due to heuristics */
1158 u_int32_t tcps_tfo_sndblackhole; /* TFO got blackholed in the sending direction */
1159 u_int32_t tcps_mss_to_default; /* Change MSS to default using link status report */
1160 u_int32_t tcps_mss_to_medium; /* Change MSS to medium using link status report */
1161 u_int32_t tcps_mss_to_low; /* Change MSS to low using link status report */
1162 u_int32_t tcps_ecn_fallback_droprst; /* ECN fallback caused by connection drop due to RST */
1163 u_int32_t tcps_ecn_fallback_droprxmt; /* ECN fallback due to drop after multiple retransmits */
1164 u_int32_t tcps_ecn_fallback_synrst; /* ECN fallback due to rst after syn */
1165
1166 u_int32_t tcps_mptcp_rcvmemdrop; /* MPTCP packets dropped for lack of memory */
1167 u_int32_t tcps_mptcp_rcvduppack; /* MPTCP duplicate-only packets received */
1168 u_int32_t tcps_mptcp_rcvpackafterwin; /* MPTCP packets with data after window */
1169
1170 /* TCP timer statistics */
1171 u_int32_t tcps_timer_drift_le_1_ms; /* Timer drift less or equal to 1 ms */
1172 u_int32_t tcps_timer_drift_le_10_ms; /* Timer drift less or equal to 10 ms */
1173 u_int32_t tcps_timer_drift_le_20_ms; /* Timer drift less or equal to 20 ms */
1174 u_int32_t tcps_timer_drift_le_50_ms; /* Timer drift less or equal to 50 ms */
1175 u_int32_t tcps_timer_drift_le_100_ms; /* Timer drift less or equal to 100 ms */
1176 u_int32_t tcps_timer_drift_le_200_ms; /* Timer drift less or equal to 200 ms */
1177 u_int32_t tcps_timer_drift_le_500_ms; /* Timer drift less or equal to 500 ms */
1178 u_int32_t tcps_timer_drift_le_1000_ms; /* Timer drift less or equal to 1000 ms */
1179 u_int32_t tcps_timer_drift_gt_1000_ms; /* Timer drift greater than 1000 ms */
1180
1181 u_int32_t tcps_mptcp_handover_attempt; /* Total number of MPTCP-attempts using handover mode */
1182 u_int32_t tcps_mptcp_interactive_attempt; /* Total number of MPTCP-attempts using interactive mode */
1183 u_int32_t tcps_mptcp_aggregate_attempt; /* Total number of MPTCP-attempts using aggregate mode */
1184 u_int32_t tcps_mptcp_fp_handover_attempt; /* Same as previous three but only for first-party apps */
1185 u_int32_t tcps_mptcp_fp_interactive_attempt;
1186 u_int32_t tcps_mptcp_fp_aggregate_attempt;
1187 u_int32_t tcps_mptcp_heuristic_fallback; /* Total number of MPTCP-connections that fell back due to heuristics */
1188 u_int32_t tcps_mptcp_fp_heuristic_fallback; /* Same as previous but for first-party apps */
1189 u_int32_t tcps_mptcp_handover_success_wifi; /* Total number of successfull handover-mode connections that *started* on WiFi */
1190 u_int32_t tcps_mptcp_handover_success_cell; /* Total number of successfull handover-mode connections that *started* on Cell */
1191 u_int32_t tcps_mptcp_interactive_success; /* Total number of interactive-mode connections that negotiated MPTCP */
1192 u_int32_t tcps_mptcp_aggregate_success; /* Same as previous but for aggregate */
1193 u_int32_t tcps_mptcp_fp_handover_success_wifi; /* Same as previous four, but for first-party apps */
1194 u_int32_t tcps_mptcp_fp_handover_success_cell;
1195 u_int32_t tcps_mptcp_fp_interactive_success;
1196 u_int32_t tcps_mptcp_fp_aggregate_success;
1197 u_int32_t tcps_mptcp_handover_cell_from_wifi; /* Total number of connections that use cell in handover-mode (coming from WiFi) */
1198 u_int32_t tcps_mptcp_handover_wifi_from_cell; /* Total number of connections that use WiFi in handover-mode (coming from cell) */
1199 u_int32_t tcps_mptcp_interactive_cell_from_wifi; /* Total number of connections that use cell in interactive mode (coming from WiFi) */
1200 u_int64_t tcps_mptcp_handover_cell_bytes; /* Total number of bytes sent on cell in handover-mode (on new subflows, ignoring initial one) */
1201 u_int64_t tcps_mptcp_interactive_cell_bytes; /* Same as previous but for interactive */
1202 u_int64_t tcps_mptcp_aggregate_cell_bytes;
1203 u_int64_t tcps_mptcp_handover_all_bytes; /* Total number of bytes sent in handover */
1204 u_int64_t tcps_mptcp_interactive_all_bytes;
1205 u_int64_t tcps_mptcp_aggregate_all_bytes;
1206 u_int32_t tcps_mptcp_back_to_wifi; /* Total number of connections that succeed to move traffic away from cell (when starting on cell) */
1207 u_int32_t tcps_mptcp_wifi_proxy; /* Total number of new subflows that fell back to regular TCP on cell */
1208 u_int32_t tcps_mptcp_cell_proxy; /* Total number of new subflows that fell back to regular TCP on WiFi */
1209 u_int32_t tcps_mptcp_triggered_cell; /* Total number of times an MPTCP-connection triggered cell bringup */
1210};
1211
1212
1213struct tcpstat_local {
1214 u_int64_t badformat;
1215 u_int64_t unspecv6;
1216 u_int64_t synfin;
1217 u_int64_t badformatipsec;
1218 u_int64_t noconnnolist;
1219 u_int64_t noconnlist;
1220 u_int64_t listbadsyn;
1221 u_int64_t icmp6unreach;
1222 u_int64_t deprecate6;
1223 u_int64_t ooopacket;
1224 u_int64_t rstinsynrcv;
1225 u_int64_t dospacket;
1226 u_int64_t cleanup;
1227 u_int64_t synwindow;
1228};
1229
1230#pragma pack(4)
1231
1232/*
1233 * TCB structure exported to user-land via sysctl(3).
1234 * Evil hack: declare only if in_pcb.h and sys/socketvar.h have been
1235 * included. Not all of our clients do.
1236 */
1237
1238struct xtcpcb {
1239 u_int32_t xt_len;
1240#ifdef KERNEL_PRIVATE
1241 struct inpcb_compat xt_inp;
1242#else
1243 struct inpcb xt_inp;
1244#endif
1245#ifdef KERNEL_PRIVATE
1246 struct otcpcb xt_tp;
1247#else
1248 struct tcpcb xt_tp;
1249#endif
1250 struct xsocket xt_socket;
1251 u_quad_t xt_alignment_hack;
1252};
1253
1254#if !CONFIG_EMBEDDED
1255
1256struct xtcpcb64 {
1257 u_int32_t xt_len;
1258 struct xinpcb64 xt_inpcb;
1259
1260 u_int64_t t_segq;
1261 int t_dupacks; /* consecutive dup acks recd */
1262
1263 int t_timer[TCPT_NTIMERS_EXT]; /* tcp timers */
1264
1265 int t_state; /* state of this connection */
1266 u_int t_flags;
1267
1268 int t_force; /* 1 if forcing out a byte */
1269
1270 tcp_seq snd_una; /* send unacknowledged */
1271 tcp_seq snd_max; /* highest sequence number sent;
1272 * used to recognize retransmits
1273 */
1274 tcp_seq snd_nxt; /* send next */
1275 tcp_seq snd_up; /* send urgent pointer */
1276
1277 tcp_seq snd_wl1; /* window update seg seq number */
1278 tcp_seq snd_wl2; /* window update seg ack number */
1279 tcp_seq iss; /* initial send sequence number */
1280 tcp_seq irs; /* initial receive sequence number */
1281
1282 tcp_seq rcv_nxt; /* receive next */
1283 tcp_seq rcv_adv; /* advertised window */
1284 u_int32_t rcv_wnd; /* receive window */
1285 tcp_seq rcv_up; /* receive urgent pointer */
1286
1287 u_int32_t snd_wnd; /* send window */
1288 u_int32_t snd_cwnd; /* congestion-controlled window */
1289 u_int32_t snd_ssthresh; /* snd_cwnd size threshold for
1290 * for slow start exponential to
1291 * linear switch
1292 */
1293 u_int t_maxopd; /* mss plus options */
1294
1295 u_int32_t t_rcvtime; /* time at which a packet was received */
1296 u_int32_t t_starttime; /* time connection was established */
1297 int t_rtttime; /* round trip time */
1298 tcp_seq t_rtseq; /* sequence number being timed */
1299
1300 int t_rxtcur; /* current retransmit value (ticks) */
1301 u_int t_maxseg; /* maximum segment size */
1302 int t_srtt; /* smoothed round-trip time */
1303 int t_rttvar; /* variance in round-trip time */
1304
1305 int t_rxtshift; /* log(2) of rexmt exp. backoff */
1306 u_int t_rttmin; /* minimum rtt allowed */
1307 u_int32_t t_rttupdated; /* number of times rtt sampled */
1308 u_int32_t max_sndwnd; /* largest window peer has offered */
1309
1310 int t_softerror; /* possible error not yet reported */
1311/* out-of-band data */
1312 char t_oobflags; /* have some */
1313 char t_iobc; /* input character */
1314/* RFC 1323 variables */
1315 u_char snd_scale; /* window scaling for send window */
1316 u_char rcv_scale; /* window scaling for recv window */
1317 u_char request_r_scale; /* pending window scaling */
1318 u_char requested_s_scale;
1319 u_int32_t ts_recent; /* timestamp echo data */
1320
1321 u_int32_t ts_recent_age; /* when last updated */
1322 tcp_seq last_ack_sent;
1323/* RFC 1644 variables */
1324 tcp_cc cc_send; /* send connection count */
1325 tcp_cc cc_recv; /* receive connection count */
1326 tcp_seq snd_recover; /* for use in fast recovery */
1327/* experimental */
1328 u_int32_t snd_cwnd_prev; /* cwnd prior to retransmit */
1329 u_int32_t snd_ssthresh_prev; /* ssthresh prior to retransmit */
1330 u_int32_t t_badrxtwin; /* window for retransmit recovery */
1331
1332 u_quad_t xt_alignment_hack;
1333};
1334
1335#endif /* !CONFIG_EMBEDDED */
1336
1337#ifdef PRIVATE
1338
1339struct xtcpcb_n {
1340 u_int32_t xt_len;
1341 u_int32_t xt_kind; /* XSO_TCPCB */
1342
1343 u_int64_t t_segq;
1344 int t_dupacks; /* consecutive dup acks recd */
1345
1346 int t_timer[TCPT_NTIMERS_EXT]; /* tcp timers */
1347
1348 int t_state; /* state of this connection */
1349 u_int t_flags;
1350
1351 int t_force; /* 1 if forcing out a byte */
1352
1353 tcp_seq snd_una; /* send unacknowledged */
1354 tcp_seq snd_max; /* highest sequence number sent;
1355 * used to recognize retransmits
1356 */
1357 tcp_seq snd_nxt; /* send next */
1358 tcp_seq snd_up; /* send urgent pointer */
1359
1360 tcp_seq snd_wl1; /* window update seg seq number */
1361 tcp_seq snd_wl2; /* window update seg ack number */
1362 tcp_seq iss; /* initial send sequence number */
1363 tcp_seq irs; /* initial receive sequence number */
1364
1365 tcp_seq rcv_nxt; /* receive next */
1366 tcp_seq rcv_adv; /* advertised window */
1367 u_int32_t rcv_wnd; /* receive window */
1368 tcp_seq rcv_up; /* receive urgent pointer */
1369
1370 u_int32_t snd_wnd; /* send window */
1371 u_int32_t snd_cwnd; /* congestion-controlled window */
1372 u_int32_t snd_ssthresh; /* snd_cwnd size threshold for
1373 * for slow start exponential to
1374 * linear switch
1375 */
1376 u_int t_maxopd; /* mss plus options */
1377
1378 u_int32_t t_rcvtime; /* time at which a packet was received */
1379 u_int32_t t_starttime; /* time connection was established */
1380 int t_rtttime; /* round trip time */
1381 tcp_seq t_rtseq; /* sequence number being timed */
1382
1383 int t_rxtcur; /* current retransmit value (ticks) */
1384 u_int t_maxseg; /* maximum segment size */
1385 int t_srtt; /* smoothed round-trip time */
1386 int t_rttvar; /* variance in round-trip time */
1387
1388 int t_rxtshift; /* log(2) of rexmt exp. backoff */
1389 u_int t_rttmin; /* minimum rtt allowed */
1390 u_int32_t t_rttupdated; /* number of times rtt sampled */
1391 u_int32_t max_sndwnd; /* largest window peer has offered */
1392
1393 int t_softerror; /* possible error not yet reported */
1394 /* out-of-band data */
1395 char t_oobflags; /* have some */
1396 char t_iobc; /* input character */
1397 /* RFC 1323 variables */
1398 u_char snd_scale; /* window scaling for send window */
1399 u_char rcv_scale; /* window scaling for recv window */
1400 u_char request_r_scale; /* pending window scaling */
1401 u_char requested_s_scale;
1402 u_int32_t ts_recent; /* timestamp echo data */
1403
1404 u_int32_t ts_recent_age; /* when last updated */
1405 tcp_seq last_ack_sent;
1406 /* RFC 1644 variables */
1407 tcp_cc cc_send; /* send connection count */
1408 tcp_cc cc_recv; /* receive connection count */
1409 tcp_seq snd_recover; /* for use in fast recovery */
1410 /* experimental */
1411 u_int32_t snd_cwnd_prev; /* cwnd prior to retransmit */
1412 u_int32_t snd_ssthresh_prev; /* ssthresh prior to retransmit */
1413};
1414
1415 /*
1416 * The rtt measured is in milliseconds as the timestamp granularity is
1417 * a millisecond. The smoothed round-trip time and estimated variance
1418 * are stored as fixed point numbers scaled by the values below.
1419 * For convenience, these scales are also used in smoothing the average
1420 * (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed).
1421 * With these scales, srtt has 5 bits to the right of the binary point,
1422 * and thus an "ALPHA" of 0.875. rttvar has 4 bits to the right of the
1423 * binary point, and is smoothed with an ALPHA of 0.75.
1424 */
1425#define TCP_RTT_SCALE 32 /* multiplier for srtt; 3 bits frac. */
1426#define TCP_RTT_SHIFT 5 /* shift for srtt; 5 bits frac. */
1427#define TCP_RTTVAR_SCALE 16 /* multiplier for rttvar; 4 bits */
1428#define TCP_RTTVAR_SHIFT 4 /* shift for rttvar; 4 bits */
1429#define TCP_DELTA_SHIFT 2 /* see tcp_input.c */
1430
1431
1432/*
1433 * TCP structure with information that gives insight into forward progress on an interface,
1434 * exported to user-land via sysctl(3).
1435 */
1436struct xtcpprogress_indicators {
1437 u_int32_t xp_numflows; /* Total number of flows */
1438 u_int32_t xp_conn_probe_fails; /* Count of connection failures */
1439 u_int32_t xp_read_probe_fails; /* Count of read probe failures */
1440 u_int32_t xp_write_probe_fails; /* Count of write failures */
1441 u_int32_t xp_recentflows; /* Total of "recent" flows */
1442 u_int32_t xp_recentflows_unacked; /* Total of "recent" flows with unacknowledged data */
1443 u_int64_t xp_recentflows_rxbytes; /* Total of "recent" flows received bytes */
1444 u_int64_t xp_recentflows_txbytes; /* Total of "recent" flows transmitted bytes */
1445 u_int64_t xp_recentflows_rxooo; /* Total of "recent" flows received out of order bytes */
1446 u_int64_t xp_recentflows_rxdup; /* Total of "recent" flows received duplicate bytes */
1447 u_int64_t xp_recentflows_retx; /* Total of "recent" flows retransmitted bytes */
1448 u_int64_t xp_reserved1; /* Expansion */
1449 u_int64_t xp_reserved2; /* Expansion */
1450 u_int64_t xp_reserved3; /* Expansion */
1451 u_int64_t xp_reserved4; /* Expansion */
1452};
1453
1454struct tcpprogressreq {
1455 u_int64_t ifindex; /* Interface index for progress indicators */
1456 u_int64_t recentflow_maxduration; /* In mach_absolute_time, max duration for flow to be counted as "recent" */
1457 u_int64_t xp_reserved1; /* Expansion */
1458 u_int64_t xp_reserved2; /* Expansion */
1459};
1460
1461#endif /* PRIVATE */
1462
1463#pragma pack()
1464
1465/*
1466 * Names for TCP sysctl objects
1467 */
1468#define TCPCTL_DO_RFC1323 1 /* use RFC-1323 extensions */
1469#define TCPCTL_DO_RFC1644 2 /* use RFC-1644 extensions */
1470#define TCPCTL_MSSDFLT 3 /* MSS default */
1471#define TCPCTL_STATS 4 /* statistics (read-only) */
1472#define TCPCTL_RTTDFLT 5 /* default RTT estimate */
1473#define TCPCTL_KEEPIDLE 6 /* keepalive idle timer */
1474#define TCPCTL_KEEPINTVL 7 /* interval to send keepalives */
1475#define TCPCTL_SENDSPACE 8 /* send buffer space */
1476#define TCPCTL_RECVSPACE 9 /* receive buffer space */
1477#define TCPCTL_KEEPINIT 10 /* timeout for establishing syn */
1478#define TCPCTL_PCBLIST 11 /* list of all outstanding PCBs */
1479#define TCPCTL_DELACKTIME 12 /* time before sending delayed ACK */
1480#define TCPCTL_V6MSSDFLT 13 /* MSS default for IPv6 */
1481#define TCPCTL_MAXID 14
1482
1483#ifdef BSD_KERNEL_PRIVATE
1484#include <sys/bitstring.h>
1485
1486#define TCP_PKTLIST_CLEAR(tp) { \
1487 (tp)->t_pktlist_head = (tp)->t_pktlist_tail = NULL; \
1488 (tp)->t_lastchain = (tp)->t_pktlist_sentlen = 0; \
1489}
1490
1491#define TCPCTL_NAMES { \
1492 { 0, 0 }, \
1493 { "rfc1323", CTLTYPE_INT }, \
1494 { "rfc1644", CTLTYPE_INT }, \
1495 { "mssdflt", CTLTYPE_INT }, \
1496 { "stats", CTLTYPE_STRUCT }, \
1497 { "rttdflt", CTLTYPE_INT }, \
1498 { "keepidle", CTLTYPE_INT }, \
1499 { "keepintvl", CTLTYPE_INT }, \
1500 { "sendspace", CTLTYPE_INT }, \
1501 { "recvspace", CTLTYPE_INT }, \
1502 { "keepinit", CTLTYPE_INT }, \
1503 { "pcblist", CTLTYPE_STRUCT }, \
1504 { "delacktime", CTLTYPE_INT }, \
1505 { "v6mssdflt", CTLTYPE_INT }, \
1506}
1507
1508#ifdef SYSCTL_DECL
1509SYSCTL_DECL(_net_inet_tcp);
1510#endif /* SYSCTL_DECL */
1511
1512extern struct inpcbhead tcb; /* head of queue of active tcpcb's */
1513extern struct inpcbinfo tcbinfo;
1514extern struct tcpstat tcpstat; /* tcp statistics */
1515extern int tcp_mssdflt; /* XXX */
1516extern int tcp_minmss;
1517#define TCP_FASTOPEN_SERVER 0x01
1518#define TCP_FASTOPEN_CLIENT 0x02
1519
1520extern int tcp_tfo_halfcnt;
1521extern int tcp_tfo_backlog;
1522extern int tcp_fastopen;
1523extern int ss_fltsz;
1524extern int ss_fltsz_local;
1525extern int tcp_do_rfc3390; /* Calculate ss_fltsz according to RFC 3390 */
1526extern int tcp_do_rfc1323;
1527extern int target_qdelay;
1528extern u_int32_t tcp_now; /* for RFC 1323 timestamps */
1529extern struct timeval tcp_uptime;
1530extern lck_spin_t *tcp_uptime_lock;
1531extern int tcp_delack_enabled;
1532extern int tcp_do_sack; /* SACK enabled/disabled */
1533extern int tcp_do_rfc3465;
1534extern int tcp_do_rfc3465_lim2;
1535extern int maxseg_unacked;
1536extern int tcp_use_newreno;
1537extern struct zone *tcp_reass_zone;
1538extern struct zone *tcp_rxt_seg_zone;
1539extern int tcp_ecn_outbound;
1540extern int tcp_ecn_inbound;
1541extern u_int32_t tcp_do_autorcvbuf;
1542extern u_int32_t tcp_autorcvbuf_max;
1543extern u_int32_t tcp_autorcvbuf_inc_shift;
1544extern int tcp_recv_bg;
1545
1546struct protosw;
1547struct domain;
1548
1549struct tcp_respond_args {
1550 unsigned int ifscope;
1551 unsigned int nocell:1,
1552 noexpensive:1,
1553 awdl_unrestricted:1,
1554 intcoproc_allowed:1;
1555};
1556
1557void tcp_canceltimers(struct tcpcb *);
1558struct tcpcb *
1559 tcp_close(struct tcpcb *);
1560void tcp_ctlinput(int, struct sockaddr *, void *, struct ifnet *);
1561int tcp_ctloutput(struct socket *, struct sockopt *);
1562struct tcpcb *
1563 tcp_drop(struct tcpcb *, int);
1564void tcp_drain(void);
1565void tcp_getrt_rtt(struct tcpcb *tp, struct rtentry *rt);
1566struct rmxp_tao *
1567 tcp_gettaocache(struct inpcb *);
1568void tcp_init(struct protosw *, struct domain *);
1569void tcp_input(struct mbuf *, int);
1570void tcp_mss(struct tcpcb *, int, unsigned int);
1571int tcp_mssopt(struct tcpcb *);
1572void tcp_drop_syn_sent(struct inpcb *, int);
1573void tcp_mtudisc(struct inpcb *, int);
1574struct tcpcb *
1575 tcp_newtcpcb(struct inpcb *);
1576int tcp_output(struct tcpcb *);
1577void tcp_respond(struct tcpcb *, void *, struct tcphdr *, struct mbuf *,
1578 tcp_seq, tcp_seq, int, struct tcp_respond_args *);
1579struct rtentry *
1580 tcp_rtlookup(struct inpcb *, unsigned int);
1581void tcp_setpersist(struct tcpcb *);
1582void tcp_gc(struct inpcbinfo *);
1583void tcp_itimer(struct inpcbinfo *ipi);
1584void tcp_check_timer_state(struct tcpcb *tp);
1585void tcp_run_timerlist(void *arg1, void *arg2);
1586
1587struct tcptemp *tcp_maketemplate(struct tcpcb *);
1588void tcp_fillheaders(struct tcpcb *, void *, void *);
1589struct tcpcb *tcp_timers(struct tcpcb *, int);
1590void tcp_trace(int, int, struct tcpcb *, void *, struct tcphdr *, int);
1591
1592void tcp_fill_info(struct tcpcb *, struct tcp_info *);
1593void tcp_sack_doack(struct tcpcb *, struct tcpopt *, struct tcphdr *,
1594 u_int32_t *);
1595extern boolean_t tcp_sack_process_dsack(struct tcpcb *, struct tcpopt *,
1596 struct tcphdr *);
1597int tcp_detect_bad_rexmt(struct tcpcb *, struct tcphdr *, struct tcpopt *,
1598 u_int32_t rxtime);
1599void tcp_update_sack_list(struct tcpcb *tp, tcp_seq rcv_laststart, tcp_seq rcv_lastend);
1600void tcp_clean_sackreport(struct tcpcb *tp);
1601void tcp_sack_adjust(struct tcpcb *tp);
1602struct sackhole *tcp_sack_output(struct tcpcb *tp, int *sack_bytes_rexmt);
1603void tcp_sack_partialack(struct tcpcb *, struct tcphdr *);
1604void tcp_free_sackholes(struct tcpcb *tp);
1605int32_t tcp_sbspace(struct tcpcb *tp);
1606void tcp_set_tso(struct tcpcb *tp, struct ifnet *ifp);
1607void tcp_set_ecn(struct tcpcb *tp, struct ifnet *ifp);
1608void tcp_reset_stretch_ack(struct tcpcb *tp);
1609extern void tcp_get_ports_used(u_int32_t, int, u_int32_t, bitstr_t *);
1610uint32_t tcp_count_opportunistic(unsigned int ifindex, u_int32_t flags);
1611uint32_t tcp_find_anypcb_byaddr(struct ifaddr *ifa);
1612void tcp_set_max_rwinscale(struct tcpcb *tp, struct socket *so, struct ifnet *ifp);
1613struct bwmeas* tcp_bwmeas_alloc(struct tcpcb *tp);
1614void tcp_bwmeas_free(struct tcpcb *tp);
1615extern int32_t timer_diff(uint32_t t1, uint32_t toff1, uint32_t t2, uint32_t toff2);
1616
1617extern void tcp_set_background_cc(struct socket *);
1618extern void tcp_set_foreground_cc(struct socket *);
1619extern void tcp_set_recv_bg(struct socket *);
1620extern void tcp_clear_recv_bg(struct socket *);
1621extern boolean_t tcp_sack_byte_islost(struct tcpcb *tp);
1622#define IS_TCP_RECV_BG(_so) \
1623 ((_so)->so_flags1 & SOF1_TRAFFIC_MGT_TCP_RECVBG)
1624
1625#if TRAFFIC_MGT
1626#define CLEAR_IAJ_STATE(_tp_) (_tp_)->iaj_rcv_ts = 0
1627void reset_acc_iaj(struct tcpcb *tp);
1628#endif /* TRAFFIC_MGT */
1629
1630int tcp_lock (struct socket *, int, void *);
1631int tcp_unlock (struct socket *, int, void *);
1632void calculate_tcp_clock(void);
1633
1634extern void tcp_keepalive_reset(struct tcpcb *);
1635extern uint32_t get_base_rtt(struct tcpcb *tp);
1636
1637#ifdef _KERN_LOCKS_H_
1638lck_mtx_t * tcp_getlock (struct socket *, int);
1639#else
1640void * tcp_getlock (struct socket *, int);
1641#endif
1642
1643extern struct pr_usrreqs tcp_usrreqs;
1644extern u_int32_t tcp_sendspace;
1645extern u_int32_t tcp_recvspace;
1646tcp_seq tcp_new_isn(struct tcpcb *);
1647
1648extern int tcp_input_checksum(int, struct mbuf *, struct tcphdr *, int, int);
1649extern void tcp_getconninfo(struct socket *, struct conninfo_tcp *);
1650extern void add_to_time_wait(struct tcpcb *, uint32_t delay);
1651extern void tcp_pmtud_revert_segment_size(struct tcpcb *tp);
1652extern void tcp_rxtseg_insert(struct tcpcb *, tcp_seq, tcp_seq);
1653extern struct tcp_rxt_seg *tcp_rxtseg_find(struct tcpcb *, tcp_seq, tcp_seq);
1654extern void tcp_rxtseg_clean(struct tcpcb *);
1655extern boolean_t tcp_rxtseg_detect_bad_rexmt(struct tcpcb *, tcp_seq);
1656extern boolean_t tcp_rxtseg_dsack_for_tlp(struct tcpcb *);
1657extern u_int32_t tcp_rxtseg_total_size(struct tcpcb *tp);
1658extern void tcp_rexmt_save_state(struct tcpcb *tp);
1659extern void tcp_interface_send_probe(u_int16_t if_index_available);
1660extern void tcp_probe_connectivity(struct ifnet *ifp, u_int32_t enable);
1661extern void tcp_get_connectivity_status(struct tcpcb *,
1662 struct tcp_conn_status *);
1663
1664extern void tcp_fill_keepalive_offload_frames(struct ifnet *,
1665 struct ifnet_keepalive_offload_frame *, u_int32_t, size_t, u_int32_t *);
1666
1667extern boolean_t tfo_enabled(const struct tcpcb *tp);
1668extern void tcp_disable_tfo(struct tcpcb *tp);
1669extern void tcp_tfo_gen_cookie(struct inpcb *inp, u_char *out, size_t blk_size);
1670#define TCP_FASTOPEN_KEYLEN 16
1671extern int tcp_freeq(struct tcpcb *tp);
1672extern errno_t tcp_notify_ack_id_valid(struct tcpcb *, struct socket *, u_int32_t);
1673extern errno_t tcp_add_notify_ack_marker(struct tcpcb *, u_int32_t);
1674extern void tcp_notify_ack_free(struct tcpcb *);
1675extern void tcp_notify_acknowledgement(struct tcpcb *, struct socket *);
1676extern void tcp_get_notify_ack_count(struct tcpcb *,
1677 struct tcp_notify_ack_complete *);
1678extern void tcp_get_notify_ack_ids(struct tcpcb *tp,
1679 struct tcp_notify_ack_complete *);
1680extern void tcp_update_mss_locked(struct socket *, struct ifnet *);
1681
1682extern int get_tcp_inp_list(struct inpcb **, int, inp_gen_t);
1683extern bool tcp_notify_ack_active(struct socket *so);
1684
1685#if MPTCP
1686extern int mptcp_input_preproc(struct tcpcb *tp, struct mbuf *m,
1687 struct tcphdr *th, int drop_hdrlen);
1688extern uint32_t mptcp_output_csum(struct mbuf *m, uint64_t dss_val,
1689 uint32_t sseq, uint16_t dlen);
1690extern int mptcp_adj_mss(struct tcpcb *, boolean_t);
1691extern void mptcp_insert_rmap(struct tcpcb *tp, struct mbuf *m, struct tcphdr *th);
1692#endif
1693
1694__private_extern__ void tcp_update_stats_per_flow(
1695 struct ifnet_stats_per_flow *, struct ifnet *);
1696
1697#endif /* BSD_KERNEL_RPIVATE */
1698
1699#endif /* _NETINET_TCP_VAR_H_ */
1700