xref: /freebsd-13-stable/sys/netinet/tcp_var.h (revision 0cf2b6fe97fbb6920aeb5e51068063a457b0bb56)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1982, 1986, 1993, 1994, 1995
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	@(#)tcp_var.h	8.4 (Berkeley) 5/24/95
32  */
33 
34 #ifndef _NETINET_TCP_VAR_H_
35 #define _NETINET_TCP_VAR_H_
36 
37 #include <netinet/tcp.h>
38 #include <netinet/tcp_fsm.h>
39 
40 #ifdef _KERNEL
41 #include <net/vnet.h>
42 #include <sys/mbuf.h>
43 #endif
44 
45 #define TCP_END_BYTE_INFO 8	/* Bytes that makeup the "end information array" */
46 /* Types of ending byte info */
47 #define TCP_EI_EMPTY_SLOT	0
48 #define TCP_EI_STATUS_CLIENT_FIN	0x1
49 #define TCP_EI_STATUS_CLIENT_RST	0x2
50 #define TCP_EI_STATUS_SERVER_FIN	0x3
51 #define TCP_EI_STATUS_SERVER_RST	0x4
52 #define TCP_EI_STATUS_RETRAN		0x5
53 #define TCP_EI_STATUS_PROGRESS		0x6
54 #define TCP_EI_STATUS_PERSIST_MAX	0x7
55 #define TCP_EI_STATUS_KEEP_MAX		0x8
56 #define TCP_EI_STATUS_DATA_A_CLOSE	0x9
57 #define TCP_EI_STATUS_RST_IN_FRONT	0xa
58 #define TCP_EI_STATUS_2MSL		0xb
59 #define TCP_EI_STATUS_MAX_VALUE		0xb
60 
61 /************************************************/
62 /* Status bits we track to assure no duplicates,
63  * the bits here are not used by the code but
64  * for human representation. To check a bit we
65  * take and shift over by 1 minus the value (1-8).
66  */
67 /************************************************/
68 #define TCP_EI_BITS_CLIENT_FIN	0x001
69 #define TCP_EI_BITS_CLIENT_RST	0x002
70 #define TCP_EI_BITS_SERVER_FIN	0x004
71 #define TCP_EI_BITS_SERVER_RST	0x008
72 #define TCP_EI_BITS_RETRAN	0x010
73 #define TCP_EI_BITS_PROGRESS	0x020
74 #define TCP_EI_BITS_PRESIST_MAX	0x040
75 #define TCP_EI_BITS_KEEP_MAX	0x080
76 #define TCP_EI_BITS_DATA_A_CLO  0x100
77 #define TCP_EI_BITS_RST_IN_FR	0x200	/* a front state reset */
78 #define TCP_EI_BITS_2MS_TIMER	0x400	/* 2 MSL timer expired */
79 
80 #if defined(_KERNEL) || defined(_WANT_TCPCB)
81 /* TCP segment queue entry */
82 struct tseg_qent {
83 	TAILQ_ENTRY(tseg_qent) tqe_q;
84 	struct	mbuf   *tqe_m;		/* mbuf contains packet */
85 	struct  mbuf   *tqe_last;	/* last mbuf in chain */
86 	tcp_seq tqe_start;		/* TCP Sequence number start */
87 	int	tqe_len;		/* TCP segment data length */
88 	uint32_t tqe_flags;		/* The flags from the th->th_flags */
89 	uint32_t tqe_mbuf_cnt;		/* Count of mbuf overhead */
90 };
91 TAILQ_HEAD(tsegqe_head, tseg_qent);
92 
93 struct sackblk {
94 	tcp_seq start;		/* start seq no. of sack block */
95 	tcp_seq end;		/* end seq no. */
96 };
97 
98 struct sackhole {
99 	tcp_seq start;		/* start seq no. of hole */
100 	tcp_seq end;		/* end seq no. */
101 	tcp_seq rxmit;		/* next seq. no in hole to be retransmitted */
102 	TAILQ_ENTRY(sackhole) scblink;	/* scoreboard linkage */
103 };
104 
105 struct sackhint {
106 	struct sackhole	*nexthole;
107 	int32_t		sack_bytes_rexmit;
108 	tcp_seq		last_sack_ack;	/* Most recent/largest sacked ack */
109 
110 	int32_t		delivered_data; /* Newly acked data from last SACK */
111 
112 	int32_t		sacked_bytes;	/* Total sacked bytes reported by the
113 					 * receiver via sack option
114 					 */
115 	uint32_t	recover_fs;	/* Flight Size at the start of Loss recovery */
116 	uint32_t	prr_delivered;	/* Total bytes delivered using PRR */
117 	uint32_t	prr_out;	/* Bytes sent during IN_RECOVERY */
118 };
119 
120 #define SEGQ_EMPTY(tp) TAILQ_EMPTY(&(tp)->t_segq)
121 
122 STAILQ_HEAD(tcp_log_stailq, tcp_log_mem);
123 
124 /*
125  * Tcp control block, one per tcp; fields:
126  * Organized for 64 byte cacheline efficiency based
127  * on common tcp_input/tcp_output processing.
128  */
129 struct tcpcb {
130 	/* Cache line 1 */
131 	struct	inpcb *t_inpcb;		/* back pointer to internet pcb */
132 	struct tcp_function_block *t_fb;/* TCP function call block */
133 	void	*t_fb_ptr;		/* Pointer to t_fb specific data */
134 	uint32_t t_maxseg:24,		/* maximum segment size */
135 		t_logstate:8;		/* State of "black box" logging */
136 	uint32_t t_port:16,		/* Tunneling (over udp) port */
137 		t_state:4,		/* state of this connection */
138 		t_idle_reduce : 1,
139 		t_delayed_ack: 7,	/* Delayed ack variable */
140 		t_fin_is_rst: 1,	/* Are fin's treated as resets */
141 		t_log_state_set: 1,
142 		bits_spare : 2;
143 	u_int	t_flags;
144 	tcp_seq	snd_una;		/* sent but unacknowledged */
145 	tcp_seq	snd_max;		/* highest sequence number sent;
146 					 * used to recognize retransmits
147 					 */
148 	tcp_seq	snd_nxt;		/* send next */
149 	tcp_seq	snd_up;			/* send urgent pointer */
150 	uint32_t  snd_wnd;		/* send window */
151 	uint32_t  snd_cwnd;		/* congestion-controlled window */
152 	uint32_t t_peakrate_thr; 	/* pre-calculated peak rate threshold */
153 	/* Cache line 2 */
154 	u_int32_t  ts_offset;		/* our timestamp offset */
155 	u_int32_t	rfbuf_ts;	/* recv buffer autoscaling timestamp */
156 	int	rcv_numsacks;		/* # distinct sack blks present */
157 	u_int	t_tsomax;		/* TSO total burst length limit in bytes */
158 	u_int	t_tsomaxsegcount;	/* TSO maximum segment count */
159 	u_int	t_tsomaxsegsize;	/* TSO maximum segment size in bytes */
160 	tcp_seq	rcv_nxt;		/* receive next */
161 	tcp_seq	rcv_adv;		/* advertised window */
162 	uint32_t  rcv_wnd;		/* receive window */
163 	u_int	t_flags2;		/* More tcpcb flags storage */
164 	int	t_srtt;			/* smoothed round-trip time */
165 	int	t_rttvar;		/* variance in round-trip time */
166 	u_int32_t  ts_recent;		/* timestamp echo data */
167 	u_char	snd_scale;		/* window scaling for send window */
168 	u_char	rcv_scale;		/* window scaling for recv window */
169 	u_char	snd_limited;		/* segments limited transmitted */
170 	u_char	request_r_scale;	/* pending window scaling */
171 	tcp_seq	last_ack_sent;
172 	u_int	t_rcvtime;		/* inactivity time */
173 	/* Cache line 3 */
174 	tcp_seq	rcv_up;			/* receive urgent pointer */
175 	int	t_segqlen;		/* segment reassembly queue length */
176 	uint32_t t_segqmbuflen;		/* Count of bytes mbufs on all entries */
177 	struct	tsegqe_head t_segq;	/* segment reassembly queue */
178 	struct mbuf      *t_in_pkt;
179 	struct mbuf	 *t_tail_pkt;
180 	struct tcp_timer *t_timers;	/* All the TCP timers in one struct */
181 	struct	vnet *t_vnet;		/* back pointer to parent vnet */
182 	uint32_t  snd_ssthresh;		/* snd_cwnd size threshold for
183 					 * for slow start exponential to
184 					 * linear switch
185 					 */
186 	tcp_seq	snd_wl1;		/* window update seg seq number */
187 	/* Cache line 4 */
188 	tcp_seq	snd_wl2;		/* window update seg ack number */
189 
190 	tcp_seq	irs;			/* initial receive sequence number */
191 	tcp_seq	iss;			/* initial send sequence number */
192 	u_int	t_acktime;		/* RACK and BBR incoming new data was acked */
193 	u_int	t_sndtime;		/* time last data was sent */
194 	u_int	ts_recent_age;		/* when last updated */
195 	tcp_seq	snd_recover;		/* for use in NewReno Fast Recovery */
196 	uint16_t cl4_spare;		/* Spare to adjust CL 4 */
197 	char	t_oobflags;		/* have some */
198 	char	t_iobc;			/* input character */
199 	int	t_rxtcur;		/* current retransmit value (ticks) */
200 
201 	int	t_rxtshift;		/* log(2) of rexmt exp. backoff */
202 	u_int	t_rtttime;		/* RTT measurement start time */
203 
204 	tcp_seq	t_rtseq;		/* sequence number being timed */
205 	u_int	t_starttime;		/* time connection was established */
206 	u_int	t_fbyte_in;		/* ticks time when first byte queued in */
207 	u_int	t_fbyte_out;		/* ticks time when first byte queued out */
208 
209 	u_int	t_pmtud_saved_maxseg;	/* pre-blackhole MSS */
210 	int	t_blackhole_enter;	/* when to enter blackhole detection */
211 	int	t_blackhole_exit;	/* when to exit blackhole detection */
212 	u_int	t_rttmin;		/* minimum rtt allowed */
213 
214 	int	t_softerror;		/* possible error not yet reported */
215 	uint32_t  max_sndwnd;		/* largest window peer has offered */
216 	/* Cache line 5 */
217 	uint32_t  snd_cwnd_prev;	/* cwnd prior to retransmit */
218 	uint32_t  snd_ssthresh_prev;	/* ssthresh prior to retransmit */
219 	tcp_seq	snd_recover_prev;	/* snd_recover prior to retransmit */
220 	int	t_sndzerowin;		/* zero-window updates sent */
221 	u_long	t_rttupdated;		/* number of times rtt sampled */
222 	int	snd_numholes;		/* number of holes seen by sender */
223 	u_int	t_badrxtwin;		/* window for retransmit recovery */
224 	TAILQ_HEAD(sackhole_head, sackhole) snd_holes;
225 					/* SACK scoreboard (sorted) */
226 	tcp_seq	snd_fack;		/* last seq number(+1) sack'd by rcv'r*/
227 	struct sackblk sackblks[MAX_SACK_BLKS]; /* seq nos. of sack blocks */
228 	struct sackhint	sackhint;	/* SACK scoreboard hint */
229 	int	t_rttlow;		/* smallest observerved RTT */
230 	int	rfbuf_cnt;		/* recv buffer autoscaling byte count */
231 	struct toedev	*tod;		/* toedev handling this connection */
232 	int	t_sndrexmitpack;	/* retransmit packets sent */
233 	int	t_rcvoopack;		/* out-of-order packets received */
234 	void	*t_toe;			/* TOE pcb pointer */
235 	struct cc_algo	*cc_algo;	/* congestion control algorithm */
236 	struct cc_var	*ccv;		/* congestion control specific vars */
237 	struct osd	*osd;		/* storage for Khelp module data */
238 	int	t_bytes_acked;		/* # bytes acked during current RTT */
239 	u_int   t_maxunacktime;
240 	u_int	t_keepinit;		/* time to establish connection */
241 	u_int	t_keepidle;		/* time before keepalive probes begin */
242 	u_int	t_keepintvl;		/* interval between keepalives */
243 	u_int	t_keepcnt;		/* number of keepalives before close */
244 	int	t_dupacks;		/* consecutive dup acks recd */
245 	int	t_lognum;		/* Number of log entries */
246 	int	t_loglimit;		/* Maximum number of log entries */
247 	int64_t	t_pacing_rate;		/* bytes / sec, -1 => unlimited */
248 	struct tcp_log_stailq t_logs;	/* Log buffer */
249 	struct tcp_log_id_node *t_lin;
250 	struct tcp_log_id_bucket *t_lib;
251 	const char *t_output_caller;	/* Function that called tcp_output */
252 	struct statsblob *t_stats;	/* Per-connection stats */
253 	uint32_t t_logsn;		/* Log "serial number" */
254 	uint32_t gput_ts;		/* Time goodput measurement started */
255 	tcp_seq gput_seq;		/* Outbound measurement seq */
256 	tcp_seq gput_ack;		/* Inbound measurement ack */
257 	int32_t t_stats_gput_prev;	/* XXXLAS: Prev gput measurement */
258 	uint32_t t_maxpeakrate;		/* max peak rate set by user, in bytes/s */
259 	uint32_t t_sndtlppack;		/* tail loss probe packets sent */
260 	uint64_t t_sndtlpbyte;		/* total tail loss probe bytes sent */
261 	uint64_t t_sndbytes;		/* total bytes sent */
262 	uint64_t t_snd_rxt_bytes;	/* total bytes retransmitted */
263 
264 	uint8_t t_tfo_client_cookie_len; /* TCP Fast Open client cookie length */
265 	uint32_t t_end_info_status;	/* Status flag of end info */
266 	unsigned int *t_tfo_pending;	/* TCP Fast Open server pending counter */
267 	union {
268 		uint8_t client[TCP_FASTOPEN_MAX_COOKIE_LEN];
269 		uint64_t server;
270 	} t_tfo_cookie;			/* TCP Fast Open cookie to send */
271 	union {
272 		uint8_t t_end_info_bytes[TCP_END_BYTE_INFO];
273 		uint64_t t_end_info;
274 	};
275 #ifdef TCPPCAP
276 	struct mbufq t_inpkts;		/* List of saved input packets. */
277 	struct mbufq t_outpkts;		/* List of saved output packets. */
278 #endif
279 };
280 #endif	/* _KERNEL || _WANT_TCPCB */
281 
282 #ifdef _KERNEL
283 struct tcptemp {
284 	u_char	tt_ipgen[40]; /* the size must be of max ip header, now IPv6 */
285 	struct	tcphdr tt_t;
286 };
287 
288 /* Enable TCP/UDP tunneling port */
289 #define TCP_TUNNELING_PORT_MIN		0
290 #define TCP_TUNNELING_PORT_MAX		65535
291 #define TCP_TUNNELING_PORT_DEFAULT	0
292 
293 /* Enable TCP/UDP tunneling port */
294 #define TCP_TUNNELING_OVERHEAD_MIN	sizeof(struct udphdr)
295 #define TCP_TUNNELING_OVERHEAD_MAX	1024
296 #define TCP_TUNNELING_OVERHEAD_DEFAULT	TCP_TUNNELING_OVERHEAD_MIN
297 
298 /* Minimum map entries limit value, if set */
299 #define TCP_MIN_MAP_ENTRIES_LIMIT	128
300 
301 /*
302  * TODO: We yet need to brave plowing in
303  * to tcp_input() and the pru_usrreq() block.
304  * Right now these go to the old standards which
305  * are somewhat ok, but in the long term may
306  * need to be changed. If we do tackle tcp_input()
307  * then we need to get rid of the tcp_do_segment()
308  * function below.
309  */
310 /* Flags for tcp functions */
311 #define TCP_FUNC_BEING_REMOVED 0x01   	/* Can no longer be referenced */
312 
313 /*
314  * If defining the optional tcp_timers, in the
315  * tfb_tcp_timer_stop call you must use the
316  * callout_async_drain() function with the
317  * tcp_timer_discard callback. You should check
318  * the return of callout_async_drain() and if 0
319  * increment tt_draincnt. Since the timer sub-system
320  * does not know your callbacks you must provide a
321  * stop_all function that loops through and calls
322  * tcp_timer_stop() with each of your defined timers.
323  * Adding a tfb_tcp_handoff_ok function allows the socket
324  * option to change stacks to query you even if the
325  * connection is in a later stage. You return 0 to
326  * say you can take over and run your stack, you return
327  * non-zero (an error number) to say no you can't.
328  * If the function is undefined you can only change
329  * in the early states (before connect or listen).
330  * tfb_tcp_fb_fini is changed to add a flag to tell
331  * the old stack if the tcb is being destroyed or
332  * not. A one in the flag means the TCB is being
333  * destroyed, a zero indicates its transitioning to
334  * another stack (via socket option).
335  */
336 struct tcp_function_block {
337 	char tfb_tcp_block_name[TCP_FUNCTION_NAME_LEN_MAX];
338 	int	(*tfb_tcp_output)(struct tcpcb *);
339 	int	(*tfb_tcp_output_wtime)(struct tcpcb *, const struct timeval *);
340 	void	(*tfb_tcp_do_segment)(struct mbuf *, struct tcphdr *,
341 			    struct socket *, struct tcpcb *,
342 		        int, int, uint8_t);
343 	int     (*tfb_do_queued_segments)(struct socket *, struct tcpcb *, int);
344 	int      (*tfb_do_segment_nounlock)(struct mbuf *, struct tcphdr *,
345 			    struct socket *, struct tcpcb *,
346 			    int, int, uint8_t,
347 			    int, struct timeval *);
348 	void	(*tfb_tcp_hpts_do_segment)(struct mbuf *, struct tcphdr *,
349 			    struct socket *, struct tcpcb *,
350 			    int, int, uint8_t,
351 			    int, struct timeval *);
352 	int     (*tfb_tcp_ctloutput)(struct socket *so, struct sockopt *sopt,
353 			    struct inpcb *inp, struct tcpcb *tp);
354 	/* Optional memory allocation/free routine */
355 	int	(*tfb_tcp_fb_init)(struct tcpcb *);
356 	void	(*tfb_tcp_fb_fini)(struct tcpcb *, int);
357 	/* Optional timers, must define all if you define one */
358 	int	(*tfb_tcp_timer_stop_all)(struct tcpcb *);
359 	void	(*tfb_tcp_timer_activate)(struct tcpcb *,
360 			    uint32_t, u_int);
361 	int	(*tfb_tcp_timer_active)(struct tcpcb *, uint32_t);
362 	void	(*tfb_tcp_timer_stop)(struct tcpcb *, uint32_t);
363 	void	(*tfb_tcp_rexmit_tmr)(struct tcpcb *);
364 	int	(*tfb_tcp_handoff_ok)(struct tcpcb *);
365 	void	(*tfb_tcp_mtu_chg)(struct tcpcb *);
366 	int	(*tfb_pru_options)(struct tcpcb *, int);
367 	void	(*tfb_hwtls_change)(struct tcpcb *, int);
368 	volatile uint32_t tfb_refcnt;
369 	uint32_t  tfb_flags;
370 	uint8_t	tfb_id;
371 };
372 
373 struct tcp_function {
374 	TAILQ_ENTRY(tcp_function)	tf_next;
375 	char				tf_name[TCP_FUNCTION_NAME_LEN_MAX];
376 	struct tcp_function_block	*tf_fb;
377 };
378 
379 TAILQ_HEAD(tcp_funchead, tcp_function);
380 #endif	/* _KERNEL */
381 
382 /*
383  * Flags and utility macros for the t_flags field.
384  */
385 #define	TF_ACKNOW	0x00000001	/* ack peer immediately */
386 #define	TF_DELACK	0x00000002	/* ack, but try to delay it */
387 #define	TF_NODELAY	0x00000004	/* don't delay packets to coalesce */
388 #define	TF_NOOPT	0x00000008	/* don't use tcp options */
389 #define	TF_SENTFIN	0x00000010	/* have sent FIN */
390 #define	TF_REQ_SCALE	0x00000020	/* have/will request window scaling */
391 #define	TF_RCVD_SCALE	0x00000040	/* other side has requested scaling */
392 #define	TF_REQ_TSTMP	0x00000080	/* have/will request timestamps */
393 #define	TF_RCVD_TSTMP	0x00000100	/* a timestamp was received in SYN */
394 #define	TF_SACK_PERMIT	0x00000200	/* other side said I could SACK */
395 #define	TF_NEEDSYN	0x00000400	/* send SYN (implicit state) */
396 #define	TF_NEEDFIN	0x00000800	/* send FIN (implicit state) */
397 #define	TF_NOPUSH	0x00001000	/* don't push */
398 #define	TF_PREVVALID	0x00002000	/* saved values for bad rxmit valid
399 					 * Note: accessing and restoring from
400 					 * these may only be done in the 1st
401 					 * RTO recovery round (t_rxtshift == 1)
402 					 */
403 #define	TF_WAKESOR	0x00004000	/* wake up receive socket */
404 #define	TF_GPUTINPROG	0x00008000	/* Goodput measurement in progress */
405 #define	TF_MORETOCOME	0x00010000	/* More data to be appended to sock */
406 #define	TF_LQ_OVERFLOW	0x00020000	/* listen queue overflow */
407 #define	TF_LASTIDLE	0x00040000	/* connection was previously idle */
408 #define	TF_RXWIN0SENT	0x00080000	/* sent a receiver win 0 in response */
409 #define	TF_FASTRECOVERY	0x00100000	/* in NewReno Fast Recovery */
410 #define	TF_WASFRECOVERY	0x00200000	/* was in NewReno Fast Recovery */
411 #define	TF_SIGNATURE	0x00400000	/* require MD5 digests (RFC2385) */
412 #define	TF_FORCEDATA	0x00800000	/* force out a byte */
413 #define	TF_TSO		0x01000000	/* TSO enabled on this connection */
414 #define	TF_TOE		0x02000000	/* this connection is offloaded */
415 #define	TF_UNUSED0	0x04000000	/* unused */
416 #define	TF_UNUSED1	0x08000000	/* unused */
417 #define	TF_UNUSED2	0x10000000	/* unused */
418 #define	TF_CONGRECOVERY	0x20000000	/* congestion recovery mode */
419 #define	TF_WASCRECOVERY	0x40000000	/* was in congestion recovery */
420 #define	TF_FASTOPEN	0x80000000	/* TCP Fast Open indication */
421 
422 #define	IN_FASTRECOVERY(t_flags)	(t_flags & TF_FASTRECOVERY)
423 #define	ENTER_FASTRECOVERY(t_flags)	t_flags |= TF_FASTRECOVERY
424 #define	EXIT_FASTRECOVERY(t_flags)	t_flags &= ~TF_FASTRECOVERY
425 
426 #define	IN_CONGRECOVERY(t_flags)	(t_flags & TF_CONGRECOVERY)
427 #define	ENTER_CONGRECOVERY(t_flags)	t_flags |= TF_CONGRECOVERY
428 #define	EXIT_CONGRECOVERY(t_flags)	t_flags &= ~TF_CONGRECOVERY
429 
430 #define	IN_RECOVERY(t_flags) (t_flags & (TF_CONGRECOVERY | TF_FASTRECOVERY))
431 #define	ENTER_RECOVERY(t_flags) t_flags |= (TF_CONGRECOVERY | TF_FASTRECOVERY)
432 #define	EXIT_RECOVERY(t_flags) t_flags &= ~(TF_CONGRECOVERY | TF_FASTRECOVERY)
433 
434 #if defined(_KERNEL)
435 #if !defined(TCP_RFC7413)
436 #define	IS_FASTOPEN(t_flags)		(false)
437 #else
438 #define	IS_FASTOPEN(t_flags)		(t_flags & TF_FASTOPEN)
439 #endif
440 #endif
441 
442 #define	BYTES_THIS_ACK(tp, th)	(th->th_ack - tp->snd_una)
443 
444 /*
445  * Flags for the t_oobflags field.
446  */
447 #define	TCPOOB_HAVEDATA	0x01
448 #define	TCPOOB_HADDATA	0x02
449 
450 /*
451  * Flags for the extended TCP flags field, t_flags2
452  */
453 #define	TF2_PLPMTU_BLACKHOLE	0x00000001 /* Possible PLPMTUD Black Hole. */
454 #define	TF2_PLPMTU_PMTUD	0x00000002 /* Allowed to attempt PLPMTUD. */
455 #define	TF2_PLPMTU_MAXSEGSNT	0x00000004 /* Last seg sent was full seg. */
456 #define	TF2_LOG_AUTO		0x00000008 /* Session is auto-logging. */
457 #define TF2_DROP_AF_DATA 	0x00000010 /* Drop after all data ack'd */
458 #define	TF2_ECN_PERMIT		0x00000020 /* connection ECN-ready */
459 #define	TF2_ECN_SND_CWR		0x00000040 /* ECN CWR in queue */
460 #define	TF2_ECN_SND_ECE		0x00000080 /* ECN ECE in queue */
461 #define	TF2_ACE_PERMIT		0x00000100 /* Accurate ECN mode */
462 #define TF2_FBYTES_COMPLETE	0x00000400 /* We have first bytes in and out */
463 /*
464  * Structure to hold TCP options that are only used during segment
465  * processing (in tcp_input), but not held in the tcpcb.
466  * It's basically used to reduce the number of parameters
467  * to tcp_dooptions and tcp_addoptions.
468  * The binary order of the to_flags is relevant for packing of the
469  * options in tcp_addoptions.
470  */
471 struct tcpopt {
472 	u_int32_t	to_flags;	/* which options are present */
473 #define	TOF_MSS		0x0001		/* maximum segment size */
474 #define	TOF_SCALE	0x0002		/* window scaling */
475 #define	TOF_SACKPERM	0x0004		/* SACK permitted */
476 #define	TOF_TS		0x0010		/* timestamp */
477 #define	TOF_SIGNATURE	0x0040		/* TCP-MD5 signature option (RFC2385) */
478 #define	TOF_SACK	0x0080		/* Peer sent SACK option */
479 #define	TOF_FASTOPEN	0x0100		/* TCP Fast Open (TFO) cookie */
480 #define	TOF_MAXOPT	0x0200
481 	u_int32_t	to_tsval;	/* new timestamp */
482 	u_int32_t	to_tsecr;	/* reflected timestamp */
483 	u_char		*to_sacks;	/* pointer to the first SACK blocks */
484 	u_char		*to_signature;	/* pointer to the TCP-MD5 signature */
485 	u_int8_t	*to_tfo_cookie; /* pointer to the TFO cookie */
486 	u_int16_t	to_mss;		/* maximum segment size */
487 	u_int8_t	to_wscale;	/* window scaling */
488 	u_int8_t	to_nsacks;	/* number of SACK blocks */
489 	u_int8_t	to_tfo_len;	/* TFO cookie length */
490 	u_int32_t	to_spare;	/* UTO */
491 };
492 
493 /*
494  * Flags for tcp_dooptions.
495  */
496 #define	TO_SYN		0x01		/* parse SYN-only options */
497 
498 struct hc_metrics_lite {	/* must stay in sync with hc_metrics */
499 	uint32_t	rmx_mtu;	/* MTU for this path */
500 	uint32_t	rmx_ssthresh;	/* outbound gateway buffer limit */
501 	uint32_t	rmx_rtt;	/* estimated round trip time */
502 	uint32_t	rmx_rttvar;	/* estimated rtt variance */
503 	uint32_t	rmx_cwnd;	/* congestion window */
504 	uint32_t	rmx_sendpipe;   /* outbound delay-bandwidth product */
505 	uint32_t	rmx_recvpipe;   /* inbound delay-bandwidth product */
506 };
507 
508 /*
509  * Used by tcp_maxmtu() to communicate interface specific features
510  * and limits at the time of connection setup.
511  */
512 struct tcp_ifcap {
513 	int	ifcap;
514 	u_int	tsomax;
515 	u_int	tsomaxsegcount;
516 	u_int	tsomaxsegsize;
517 };
518 
519 #ifndef _NETINET_IN_PCB_H_
520 struct in_conninfo;
521 #endif /* _NETINET_IN_PCB_H_ */
522 
523 struct tcptw {
524 	struct inpcb	*tw_inpcb;	/* XXX back pointer to internet pcb */
525 	uint32_t  t_port:16,		/* UDP port number if TCPoUDP */
526 		t_unused:16;
527 	tcp_seq		snd_nxt;
528 	tcp_seq		rcv_nxt;
529 	tcp_seq		iss;
530 	tcp_seq		irs;
531 	u_short		last_win;	/* cached window value */
532 	short		tw_so_options;	/* copy of so_options */
533 	struct ucred	*tw_cred;	/* user credentials */
534 	u_int32_t	t_recent;
535 	u_int32_t	ts_offset;	/* our timestamp offset */
536 	u_int		t_starttime;
537 	int		tw_time;
538 	TAILQ_ENTRY(tcptw) tw_2msl;
539 	void		*tw_pspare;	/* TCP_SIGNATURE */
540 	u_int		tw_flags;	/* tcpcb t_flags */
541 };
542 
543 #define	intotcpcb(ip)	((struct tcpcb *)(ip)->inp_ppcb)
544 #define	intotw(ip)	((struct tcptw *)(ip)->inp_ppcb)
545 #define	sototcpcb(so)	(intotcpcb(sotoinpcb(so)))
546 
547 /*
548  * The smoothed round-trip time and estimated variance
549  * are stored as fixed point numbers scaled by the values below.
550  * For convenience, these scales are also used in smoothing the average
551  * (smoothed = (1/scale)sample + ((scale-1)/scale)smoothed).
552  * With these scales, srtt has 3 bits to the right of the binary point,
553  * and thus an "ALPHA" of 0.875.  rttvar has 2 bits to the right of the
554  * binary point, and is smoothed with an ALPHA of 0.75.
555  */
556 #define	TCP_RTT_SCALE		32	/* multiplier for srtt; 5 bits frac. */
557 #define	TCP_RTT_SHIFT		5	/* shift for srtt; 5 bits frac. */
558 #define	TCP_RTTVAR_SCALE	16	/* multiplier for rttvar; 4 bits */
559 #define	TCP_RTTVAR_SHIFT	4	/* shift for rttvar; 4 bits */
560 #define	TCP_DELTA_SHIFT		2	/* see tcp_input.c */
561 
562 /*
563  * The initial retransmission should happen at rtt + 4 * rttvar.
564  * Because of the way we do the smoothing, srtt and rttvar
565  * will each average +1/2 tick of bias.  When we compute
566  * the retransmit timer, we want 1/2 tick of rounding and
567  * 1 extra tick because of +-1/2 tick uncertainty in the
568  * firing of the timer.  The bias will give us exactly the
569  * 1.5 tick we need.  But, because the bias is
570  * statistical, we have to test that we don't drop below
571  * the minimum feasible timer (which is 2 ticks).
572  * This version of the macro adapted from a paper by Lawrence
573  * Brakmo and Larry Peterson which outlines a problem caused
574  * by insufficient precision in the original implementation,
575  * which results in inappropriately large RTO values for very
576  * fast networks.
577  */
578 #define	TCP_REXMTVAL(tp) \
579 	max((tp)->t_rttmin, (((tp)->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT))  \
580 	  + (tp)->t_rttvar) >> TCP_DELTA_SHIFT)
581 
582 /*
583  * TCP statistics.
584  * Many of these should be kept per connection,
585  * but that's inconvenient at the moment.
586  */
587 struct	tcpstat {
588 	uint64_t tcps_connattempt;	/* connections initiated */
589 	uint64_t tcps_accepts;		/* connections accepted */
590 	uint64_t tcps_connects;		/* connections established */
591 	uint64_t tcps_drops;		/* connections dropped */
592 	uint64_t tcps_conndrops;	/* embryonic connections dropped */
593 	uint64_t tcps_minmssdrops;	/* average minmss too low drops */
594 	uint64_t tcps_closed;		/* conn. closed (includes drops) */
595 	uint64_t tcps_segstimed;	/* segs where we tried to get rtt */
596 	uint64_t tcps_rttupdated;	/* times we succeeded */
597 	uint64_t tcps_delack;		/* delayed acks sent */
598 	uint64_t tcps_timeoutdrop;	/* conn. dropped in rxmt timeout */
599 	uint64_t tcps_rexmttimeo;	/* retransmit timeouts */
600 	uint64_t tcps_persisttimeo;	/* persist timeouts */
601 	uint64_t tcps_keeptimeo;	/* keepalive timeouts */
602 	uint64_t tcps_keepprobe;	/* keepalive probes sent */
603 	uint64_t tcps_keepdrops;	/* connections dropped in keepalive */
604 
605 	uint64_t tcps_sndtotal;		/* total packets sent */
606 	uint64_t tcps_sndpack;		/* data packets sent */
607 	uint64_t tcps_sndbyte;		/* data bytes sent */
608 	uint64_t tcps_sndrexmitpack;	/* data packets retransmitted */
609 	uint64_t tcps_sndrexmitbyte;	/* data bytes retransmitted */
610 	uint64_t tcps_sndrexmitbad;	/* unnecessary packet retransmissions */
611 	uint64_t tcps_sndacks;		/* ack-only packets sent */
612 	uint64_t tcps_sndprobe;		/* window probes sent */
613 	uint64_t tcps_sndurg;		/* packets sent with URG only */
614 	uint64_t tcps_sndwinup;		/* window update-only packets sent */
615 	uint64_t tcps_sndctrl;		/* control (SYN|FIN|RST) packets sent */
616 
617 	uint64_t tcps_rcvtotal;		/* total packets received */
618 	uint64_t tcps_rcvpack;		/* packets received in sequence */
619 	uint64_t tcps_rcvbyte;		/* bytes received in sequence */
620 	uint64_t tcps_rcvbadsum;	/* packets received with ccksum errs */
621 	uint64_t tcps_rcvbadoff;	/* packets received with bad offset */
622 	uint64_t tcps_rcvreassfull;	/* packets dropped for no reass space */
623 	uint64_t tcps_rcvshort;		/* packets received too short */
624 	uint64_t tcps_rcvduppack;	/* duplicate-only packets received */
625 	uint64_t tcps_rcvdupbyte;	/* duplicate-only bytes received */
626 	uint64_t tcps_rcvpartduppack;	/* packets with some duplicate data */
627 	uint64_t tcps_rcvpartdupbyte;	/* dup. bytes in part-dup. packets */
628 	uint64_t tcps_rcvoopack;	/* out-of-order packets received */
629 	uint64_t tcps_rcvoobyte;	/* out-of-order bytes received */
630 	uint64_t tcps_rcvpackafterwin;	/* packets with data after window */
631 	uint64_t tcps_rcvbyteafterwin;	/* bytes rcvd after window */
632 	uint64_t tcps_rcvafterclose;	/* packets rcvd after "close" */
633 	uint64_t tcps_rcvwinprobe;	/* rcvd window probe packets */
634 	uint64_t tcps_rcvdupack;	/* rcvd duplicate acks */
635 	uint64_t tcps_rcvacktoomuch;	/* rcvd acks for unsent data */
636 	uint64_t tcps_rcvackpack;	/* rcvd ack packets */
637 	uint64_t tcps_rcvackbyte;	/* bytes acked by rcvd acks */
638 	uint64_t tcps_rcvwinupd;	/* rcvd window update packets */
639 	uint64_t tcps_pawsdrop;		/* segments dropped due to PAWS */
640 	uint64_t tcps_predack;		/* times hdr predict ok for acks */
641 	uint64_t tcps_preddat;		/* times hdr predict ok for data pkts */
642 	uint64_t tcps_pcbcachemiss;
643 	uint64_t tcps_cachedrtt;	/* times cached RTT in route updated */
644 	uint64_t tcps_cachedrttvar;	/* times cached rttvar updated */
645 	uint64_t tcps_cachedssthresh;	/* times cached ssthresh updated */
646 	uint64_t tcps_usedrtt;		/* times RTT initialized from route */
647 	uint64_t tcps_usedrttvar;	/* times RTTVAR initialized from rt */
648 	uint64_t tcps_usedssthresh;	/* times ssthresh initialized from rt*/
649 	uint64_t tcps_persistdrop;	/* timeout in persist state */
650 	uint64_t tcps_badsyn;		/* bogus SYN, e.g. premature ACK */
651 	uint64_t tcps_mturesent;	/* resends due to MTU discovery */
652 	uint64_t tcps_listendrop;	/* listen queue overflows */
653 	uint64_t tcps_badrst;		/* ignored RSTs in the window */
654 
655 	uint64_t tcps_sc_added;		/* entry added to syncache */
656 	uint64_t tcps_sc_retransmitted;	/* syncache entry was retransmitted */
657 	uint64_t tcps_sc_dupsyn;	/* duplicate SYN packet */
658 	uint64_t tcps_sc_dropped;	/* could not reply to packet */
659 	uint64_t tcps_sc_completed;	/* successful extraction of entry */
660 	uint64_t tcps_sc_bucketoverflow;/* syncache per-bucket limit hit */
661 	uint64_t tcps_sc_cacheoverflow;	/* syncache cache limit hit */
662 	uint64_t tcps_sc_reset;		/* RST removed entry from syncache */
663 	uint64_t tcps_sc_stale;		/* timed out or listen socket gone */
664 	uint64_t tcps_sc_aborted;	/* syncache entry aborted */
665 	uint64_t tcps_sc_badack;	/* removed due to bad ACK */
666 	uint64_t tcps_sc_unreach;	/* ICMP unreachable received */
667 	uint64_t tcps_sc_zonefail;	/* zalloc() failed */
668 	uint64_t tcps_sc_sendcookie;	/* SYN cookie sent */
669 	uint64_t tcps_sc_recvcookie;	/* SYN cookie received */
670 
671 	uint64_t tcps_hc_added;		/* entry added to hostcache */
672 	uint64_t tcps_hc_bucketoverflow;/* hostcache per bucket limit hit */
673 
674 	uint64_t tcps_finwait2_drops;    /* Drop FIN_WAIT_2 connection after time limit */
675 
676 	/* SACK related stats */
677 	uint64_t tcps_sack_recovery_episode; /* SACK recovery episodes */
678 	uint64_t tcps_sack_rexmits;	    /* SACK rexmit segments   */
679 	uint64_t tcps_sack_rexmit_bytes;    /* SACK rexmit bytes      */
680 	uint64_t tcps_sack_rcv_blocks;	    /* SACK blocks (options) received */
681 	uint64_t tcps_sack_send_blocks;	    /* SACK blocks (options) sent     */
682 	uint64_t tcps_sack_sboverflow;	    /* times scoreboard overflowed */
683 
684 	/* ECN related stats */
685 	uint64_t tcps_ecn_ce;		/* ECN Congestion Experienced */
686 	uint64_t tcps_ecn_ect0;		/* ECN Capable Transport */
687 	uint64_t tcps_ecn_ect1;		/* ECN Capable Transport */
688 	uint64_t tcps_ecn_shs;		/* ECN successful handshakes */
689 	uint64_t tcps_ecn_rcwnd;	/* # times ECN reduced the cwnd */
690 
691 	/* TCP_SIGNATURE related stats */
692 	uint64_t tcps_sig_rcvgoodsig;	/* Total matching signature received */
693 	uint64_t tcps_sig_rcvbadsig;	/* Total bad signature received */
694 	uint64_t tcps_sig_err_buildsig;	/* Failed to make signature */
695 	uint64_t tcps_sig_err_sigopt;	/* No signature expected by socket */
696 	uint64_t tcps_sig_err_nosigopt;	/* No signature provided by segment */
697 
698 	/* Path MTU Discovery Black Hole Detection related stats */
699 	uint64_t tcps_pmtud_blackhole_activated;	 /* Black Hole Count */
700 	uint64_t tcps_pmtud_blackhole_activated_min_mss; /* BH at min MSS Count */
701 	uint64_t tcps_pmtud_blackhole_failed;		 /* Black Hole Failure Count */
702 
703 	uint64_t tcps_tunneled_pkts;	/* Packets encap's in UDP received */
704 	uint64_t tcps_tunneled_errs;	/* Packets that had errors that were UDP encaped */
705 
706 	/* TCPS_TIME_WAIT usage stats */
707 	uint64_t tcps_tw_recycles;	/* Times time-wait was recycled. */
708 	uint64_t tcps_tw_resets;	/* Times time-wait sent a reset. */
709 	uint64_t tcps_tw_responds;	/* Times time-wait sent a valid ack. */
710 
711 	uint64_t _pad[7];
712 };
713 
714 #define	tcps_rcvmemdrop	tcps_rcvreassfull	/* compat */
715 
716 #ifdef _KERNEL
717 #define	TI_UNLOCKED	1
718 #define	TI_RLOCKED	2
719 #include <sys/counter.h>
720 
721 VNET_PCPUSTAT_DECLARE(struct tcpstat, tcpstat);	/* tcp statistics */
722 /*
723  * In-kernel consumers can use these accessor macros directly to update
724  * stats.
725  */
726 #define	TCPSTAT_ADD(name, val)	\
727     VNET_PCPUSTAT_ADD(struct tcpstat, tcpstat, name, (val))
728 #define	TCPSTAT_INC(name)	TCPSTAT_ADD(name, 1)
729 
730 /*
731  * Kernel module consumers must use this accessor macro.
732  */
733 void	kmod_tcpstat_add(int statnum, int val);
734 #define	KMOD_TCPSTAT_ADD(name, val)					\
735     kmod_tcpstat_add(offsetof(struct tcpstat, name) / sizeof(uint64_t), val)
736 #define	KMOD_TCPSTAT_INC(name)	KMOD_TCPSTAT_ADD(name, 1)
737 
738 /*
739  * Running TCP connection count by state.
740  */
741 VNET_DECLARE(counter_u64_t, tcps_states[TCP_NSTATES]);
742 #define	V_tcps_states	VNET(tcps_states)
743 #define	TCPSTATES_INC(state)	counter_u64_add(V_tcps_states[state], 1)
744 #define	TCPSTATES_DEC(state)	counter_u64_add(V_tcps_states[state], -1)
745 
746 /*
747  * TCP specific helper hook point identifiers.
748  */
749 #define	HHOOK_TCP_EST_IN		0
750 #define	HHOOK_TCP_EST_OUT		1
751 #define	HHOOK_TCP_LAST			HHOOK_TCP_EST_OUT
752 
753 struct tcp_hhook_data {
754 	struct tcpcb	*tp;
755 	struct tcphdr	*th;
756 	struct tcpopt	*to;
757 	uint32_t	len;
758 	int		tso;
759 	tcp_seq		curack;
760 };
761 #ifdef TCP_HHOOK
762 void hhook_run_tcp_est_out(struct tcpcb *tp,
763 	struct tcphdr *th, struct tcpopt *to,
764 	uint32_t len, int tso);
765 #endif
766 #endif
767 
768 /*
769  * TCB structure exported to user-land via sysctl(3).
770  *
771  * Fields prefixed with "xt_" are unique to the export structure, and fields
772  * with "t_" or other prefixes match corresponding fields of 'struct tcpcb'.
773  *
774  * Legend:
775  * (s) - used by userland utilities in src
776  * (p) - used by utilities in ports
777  * (3) - is known to be used by third party software not in ports
778  * (n) - no known usage
779  *
780  * Evil hack: declare only if in_pcb.h and sys/socketvar.h have been
781  * included.  Not all of our clients do.
782  */
783 #if defined(_NETINET_IN_PCB_H_) && defined(_SYS_SOCKETVAR_H_)
784 struct xtcpcb {
785 	ksize_t	xt_len;		/* length of this structure */
786 	struct xinpcb	xt_inp;
787 	char		xt_stack[TCP_FUNCTION_NAME_LEN_MAX];	/* (s) */
788 	char		xt_logid[TCP_LOG_ID_LEN];	/* (s) */
789 	char		xt_cc[TCP_CA_NAME_MAX];	/* (s) */
790 	int64_t		spare64[6];
791 	int32_t		t_state;		/* (s,p) */
792 	uint32_t	t_flags;		/* (s,p) */
793 	int32_t		t_sndzerowin;		/* (s) */
794 	int32_t		t_sndrexmitpack;	/* (s) */
795 	int32_t		t_rcvoopack;		/* (s) */
796 	int32_t		t_rcvtime;		/* (s) */
797 	int32_t		tt_rexmt;		/* (s) */
798 	int32_t		tt_persist;		/* (s) */
799 	int32_t		tt_keep;		/* (s) */
800 	int32_t		tt_2msl;		/* (s) */
801 	int32_t		tt_delack;		/* (s) */
802 	int32_t		t_logstate;		/* (3) */
803 	uint32_t	t_snd_cwnd;		/* (s) */
804 	uint32_t	t_snd_ssthresh;		/* (s) */
805 	uint32_t	t_maxseg;		/* (s) */
806 	uint32_t	t_rcv_wnd;		/* (s) */
807 	uint32_t	t_snd_wnd;		/* (s) */
808 	uint32_t	xt_ecn;			/* (s) */
809 	uint16_t	xt_encaps_port;		/* (s) */
810 	int16_t		spare16;
811 	int32_t		spare32[25];
812 } __aligned(8);
813 
814 #ifdef _KERNEL
815 void	tcp_inptoxtp(const struct inpcb *, struct xtcpcb *);
816 #endif
817 #endif
818 
819 /*
820  * TCP function information (name-to-id mapping, aliases, and refcnt)
821  * exported to user-land via sysctl(3).
822  */
823 struct tcp_function_info {
824 	uint32_t	tfi_refcnt;
825 	uint8_t		tfi_id;
826 	char		tfi_name[TCP_FUNCTION_NAME_LEN_MAX];
827 	char		tfi_alias[TCP_FUNCTION_NAME_LEN_MAX];
828 };
829 
830 /*
831  * Identifiers for TCP sysctl nodes
832  */
833 #define	TCPCTL_DO_RFC1323	1	/* use RFC-1323 extensions */
834 #define	TCPCTL_MSSDFLT		3	/* MSS default */
835 #define TCPCTL_STATS		4	/* statistics */
836 #define	TCPCTL_RTTDFLT		5	/* default RTT estimate */
837 #define	TCPCTL_KEEPIDLE		6	/* keepalive idle timer */
838 #define	TCPCTL_KEEPINTVL	7	/* interval to send keepalives */
839 #define	TCPCTL_SENDSPACE	8	/* send buffer space */
840 #define	TCPCTL_RECVSPACE	9	/* receive buffer space */
841 #define	TCPCTL_KEEPINIT		10	/* timeout for establishing syn */
842 #define	TCPCTL_PCBLIST		11	/* list of all outstanding PCBs */
843 #define	TCPCTL_DELACKTIME	12	/* time before sending delayed ACK */
844 #define	TCPCTL_V6MSSDFLT	13	/* MSS default for IPv6 */
845 #define	TCPCTL_SACK		14	/* Selective Acknowledgement,rfc 2018 */
846 #define	TCPCTL_DROP		15	/* drop tcp connection */
847 #define	TCPCTL_STATES		16	/* connection counts by TCP state */
848 
849 #ifdef _KERNEL
850 #ifdef SYSCTL_DECL
851 SYSCTL_DECL(_net_inet_tcp);
852 SYSCTL_DECL(_net_inet_tcp_sack);
853 MALLOC_DECLARE(M_TCPLOG);
854 #endif
855 
856 VNET_DECLARE(int, tcp_log_in_vain);
857 #define	V_tcp_log_in_vain		VNET(tcp_log_in_vain)
858 
859 /*
860  * Global TCP tunables shared between different stacks.
861  * Please keep the list sorted.
862  */
863 VNET_DECLARE(int, drop_synfin);
864 VNET_DECLARE(int, path_mtu_discovery);
865 VNET_DECLARE(int, tcp_abc_l_var);
866 VNET_DECLARE(int, tcp_autorcvbuf_max);
867 VNET_DECLARE(int, tcp_autosndbuf_inc);
868 VNET_DECLARE(int, tcp_autosndbuf_max);
869 VNET_DECLARE(int, tcp_delack_enabled);
870 VNET_DECLARE(int, tcp_do_autorcvbuf);
871 VNET_DECLARE(int, tcp_do_autosndbuf);
872 VNET_DECLARE(int, tcp_do_ecn);
873 VNET_DECLARE(int, tcp_do_prr);
874 VNET_DECLARE(int, tcp_do_prr_conservative);
875 VNET_DECLARE(int, tcp_do_newcwv);
876 VNET_DECLARE(int, tcp_do_rfc1323);
877 VNET_DECLARE(int, tcp_tolerate_missing_ts);
878 VNET_DECLARE(int, tcp_do_rfc3042);
879 VNET_DECLARE(int, tcp_do_rfc3390);
880 VNET_DECLARE(int, tcp_do_rfc3465);
881 VNET_DECLARE(int, tcp_do_rfc6675_pipe);
882 VNET_DECLARE(int, tcp_do_sack);
883 VNET_DECLARE(int, tcp_do_tso);
884 VNET_DECLARE(int, tcp_ecn_maxretries);
885 VNET_DECLARE(int, tcp_initcwnd_segments);
886 VNET_DECLARE(int, tcp_insecure_rst);
887 VNET_DECLARE(int, tcp_insecure_syn);
888 VNET_DECLARE(uint32_t, tcp_map_entries_limit);
889 VNET_DECLARE(uint32_t, tcp_map_split_limit);
890 VNET_DECLARE(int, tcp_minmss);
891 VNET_DECLARE(int, tcp_mssdflt);
892 #ifdef STATS
893 VNET_DECLARE(int, tcp_perconn_stats_dflt_tpl);
894 VNET_DECLARE(int, tcp_perconn_stats_enable);
895 #endif /* STATS */
896 VNET_DECLARE(int, tcp_recvspace);
897 VNET_DECLARE(int, tcp_sack_globalholes);
898 VNET_DECLARE(int, tcp_sack_globalmaxholes);
899 VNET_DECLARE(int, tcp_sack_maxholes);
900 VNET_DECLARE(int, tcp_sc_rst_sock_fail);
901 VNET_DECLARE(int, tcp_sendspace);
902 VNET_DECLARE(int, tcp_udp_tunneling_overhead);
903 VNET_DECLARE(int, tcp_udp_tunneling_port);
904 VNET_DECLARE(struct inpcbhead, tcb);
905 VNET_DECLARE(struct inpcbinfo, tcbinfo);
906 
907 #define	V_tcp_do_prr			VNET(tcp_do_prr)
908 #define	V_tcp_do_prr_conservative	VNET(tcp_do_prr_conservative)
909 #define	V_tcp_do_newcwv			VNET(tcp_do_newcwv)
910 #define	V_drop_synfin			VNET(drop_synfin)
911 #define	V_path_mtu_discovery		VNET(path_mtu_discovery)
912 #define	V_tcb				VNET(tcb)
913 #define	V_tcbinfo			VNET(tcbinfo)
914 #define	V_tcp_abc_l_var			VNET(tcp_abc_l_var)
915 #define	V_tcp_autorcvbuf_max		VNET(tcp_autorcvbuf_max)
916 #define	V_tcp_autosndbuf_inc		VNET(tcp_autosndbuf_inc)
917 #define	V_tcp_autosndbuf_max		VNET(tcp_autosndbuf_max)
918 #define	V_tcp_delack_enabled		VNET(tcp_delack_enabled)
919 #define	V_tcp_do_autorcvbuf		VNET(tcp_do_autorcvbuf)
920 #define	V_tcp_do_autosndbuf		VNET(tcp_do_autosndbuf)
921 #define	V_tcp_do_ecn			VNET(tcp_do_ecn)
922 #define	V_tcp_do_rfc1323		VNET(tcp_do_rfc1323)
923 #define	V_tcp_tolerate_missing_ts	VNET(tcp_tolerate_missing_ts)
924 #define V_tcp_ts_offset_per_conn	VNET(tcp_ts_offset_per_conn)
925 #define	V_tcp_do_rfc3042		VNET(tcp_do_rfc3042)
926 #define	V_tcp_do_rfc3390		VNET(tcp_do_rfc3390)
927 #define	V_tcp_do_rfc3465		VNET(tcp_do_rfc3465)
928 #define	V_tcp_do_rfc6675_pipe		VNET(tcp_do_rfc6675_pipe)
929 #define	V_tcp_do_sack			VNET(tcp_do_sack)
930 #define	V_tcp_do_tso			VNET(tcp_do_tso)
931 #define	V_tcp_ecn_maxretries		VNET(tcp_ecn_maxretries)
932 #define	V_tcp_initcwnd_segments		VNET(tcp_initcwnd_segments)
933 #define	V_tcp_insecure_rst		VNET(tcp_insecure_rst)
934 #define	V_tcp_insecure_syn		VNET(tcp_insecure_syn)
935 #define	V_tcp_map_entries_limit		VNET(tcp_map_entries_limit)
936 #define	V_tcp_map_split_limit		VNET(tcp_map_split_limit)
937 #define	V_tcp_minmss			VNET(tcp_minmss)
938 #define	V_tcp_mssdflt			VNET(tcp_mssdflt)
939 #ifdef STATS
940 #define	V_tcp_perconn_stats_dflt_tpl	VNET(tcp_perconn_stats_dflt_tpl)
941 #define	V_tcp_perconn_stats_enable	VNET(tcp_perconn_stats_enable)
942 #endif /* STATS */
943 #define	V_tcp_recvspace			VNET(tcp_recvspace)
944 #define	V_tcp_sack_globalholes		VNET(tcp_sack_globalholes)
945 #define	V_tcp_sack_globalmaxholes	VNET(tcp_sack_globalmaxholes)
946 #define	V_tcp_sack_maxholes		VNET(tcp_sack_maxholes)
947 #define	V_tcp_sc_rst_sock_fail		VNET(tcp_sc_rst_sock_fail)
948 #define	V_tcp_sendspace			VNET(tcp_sendspace)
949 #define	V_tcp_udp_tunneling_overhead	VNET(tcp_udp_tunneling_overhead)
950 #define	V_tcp_udp_tunneling_port	VNET(tcp_udp_tunneling_port)
951 
952 #ifdef TCP_HHOOK
953 VNET_DECLARE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST + 1]);
954 #define	V_tcp_hhh		VNET(tcp_hhh)
955 #endif
956 
957 int	 tcp_addoptions(struct tcpopt *, u_char *);
958 int	 tcp_ccalgounload(struct cc_algo *unload_algo);
959 struct tcpcb *
960 	 tcp_close(struct tcpcb *);
961 void	 tcp_discardcb(struct tcpcb *);
962 void	 tcp_twstart(struct tcpcb *);
963 void	 tcp_twclose(struct tcptw *, int);
964 void	 tcp_ctlinput(int, struct sockaddr *, void *);
965 int	 tcp_ctloutput(struct socket *, struct sockopt *);
966 void 	 tcp_ctlinput_viaudp(int, struct sockaddr *, void *, void *);
967 struct tcpcb *
968 	 tcp_drop(struct tcpcb *, int);
969 void	 tcp_drain(void);
970 void	 tcp_init(void);
971 void	 tcp_fini(void *);
972 char	*tcp_log_addrs(struct in_conninfo *, struct tcphdr *, void *,
973 	    const void *);
974 char	*tcp_log_vain(struct in_conninfo *, struct tcphdr *, void *,
975 	    const void *);
976 int	 tcp_reass(struct tcpcb *, struct tcphdr *, tcp_seq *, int *,
977 	    struct mbuf *);
978 void	 tcp_reass_global_init(void);
979 void	 tcp_reass_flush(struct tcpcb *);
980 void	 tcp_dooptions(struct tcpopt *, u_char *, int, int);
981 void	tcp_dropwithreset(struct mbuf *, struct tcphdr *,
982 		     struct tcpcb *, int, int);
983 void	tcp_pulloutofband(struct socket *,
984 		     struct tcphdr *, struct mbuf *, int);
985 void	tcp_xmit_timer(struct tcpcb *, int);
986 void	tcp_newreno_partial_ack(struct tcpcb *, struct tcphdr *);
987 void	cc_ack_received(struct tcpcb *tp, struct tcphdr *th,
988 			    uint16_t nsegs, uint16_t type);
989 void 	cc_conn_init(struct tcpcb *tp);
990 void 	cc_post_recovery(struct tcpcb *tp, struct tcphdr *th);
991 void    cc_ecnpkt_handler(struct tcpcb *tp, struct tcphdr *th, uint8_t iptos);
992 void	cc_ecnpkt_handler_flags(struct tcpcb *tp, uint16_t flags, uint8_t iptos);
993 void	cc_cong_signal(struct tcpcb *tp, struct tcphdr *th, uint32_t type);
994 #ifdef TCP_HHOOK
995 void	hhook_run_tcp_est_in(struct tcpcb *tp,
996 			    struct tcphdr *th, struct tcpopt *to);
997 #endif
998 
999 int	 tcp_input(struct mbuf **, int *, int);
1000 int	 tcp_autorcvbuf(struct mbuf *, struct tcphdr *, struct socket *,
1001 	    struct tcpcb *, int);
1002 int	 tcp_input_with_port(struct mbuf **, int *, int, uint16_t);
1003 void	 tcp_handle_wakeup(struct tcpcb *, struct socket *);
1004 void	 tcp_do_segment(struct mbuf *, struct tcphdr *,
1005 			struct socket *, struct tcpcb *, int, int, uint8_t);
1006 
1007 int register_tcp_functions(struct tcp_function_block *blk, int wait);
1008 int register_tcp_functions_as_names(struct tcp_function_block *blk,
1009     int wait, const char *names[], int *num_names);
1010 int register_tcp_functions_as_name(struct tcp_function_block *blk,
1011     const char *name, int wait);
1012 int deregister_tcp_functions(struct tcp_function_block *blk, bool quiesce,
1013     bool force);
1014 struct tcp_function_block *find_and_ref_tcp_functions(struct tcp_function_set *fs);
1015 void tcp_switch_back_to_default(struct tcpcb *tp);
1016 struct tcp_function_block *
1017 find_and_ref_tcp_fb(struct tcp_function_block *fs);
1018 int tcp_default_ctloutput(struct socket *so, struct sockopt *sopt, struct inpcb *inp, struct tcpcb *tp);
1019 
1020 extern counter_u64_t tcp_inp_lro_direct_queue;
1021 extern counter_u64_t tcp_inp_lro_wokeup_queue;
1022 extern counter_u64_t tcp_inp_lro_compressed;
1023 extern counter_u64_t tcp_inp_lro_locks_taken;
1024 extern counter_u64_t tcp_extra_mbuf;
1025 extern counter_u64_t tcp_would_have_but;
1026 extern counter_u64_t tcp_comp_total;
1027 extern counter_u64_t tcp_uncomp_total;
1028 
1029 #ifdef NETFLIX_EXP_DETECTION
1030 /* Various SACK attack thresholds */
1031 extern int32_t tcp_force_detection;
1032 extern int32_t tcp_sack_to_ack_thresh;
1033 extern int32_t tcp_sack_to_move_thresh;
1034 extern int32_t tcp_restoral_thresh;
1035 extern int32_t tcp_sad_decay_val;
1036 extern int32_t tcp_sad_pacing_interval;
1037 extern int32_t tcp_sad_low_pps;
1038 extern int32_t tcp_map_minimum;
1039 extern int32_t tcp_attack_on_turns_on_logging;
1040 #endif
1041 extern uint32_t tcp_ack_war_time_window;
1042 extern uint32_t tcp_ack_war_cnt;
1043 
1044 uint32_t tcp_maxmtu(struct in_conninfo *, struct tcp_ifcap *);
1045 uint32_t tcp_maxmtu6(struct in_conninfo *, struct tcp_ifcap *);
1046 u_int	 tcp_maxseg(const struct tcpcb *);
1047 u_int	 tcp_fixed_maxseg(const struct tcpcb *);
1048 void	 tcp_mss_update(struct tcpcb *, int, int, struct hc_metrics_lite *,
1049 	    struct tcp_ifcap *);
1050 void	 tcp_mss(struct tcpcb *, int);
1051 int	 tcp_mssopt(struct in_conninfo *);
1052 struct inpcb *
1053 	 tcp_drop_syn_sent(struct inpcb *, int);
1054 struct tcpcb *
1055 	 tcp_newtcpcb(struct inpcb *);
1056 int	 tcp_output(struct tcpcb *);
1057 void	 tcp_state_change(struct tcpcb *, int);
1058 void	 tcp_respond(struct tcpcb *, void *,
1059 	    struct tcphdr *, struct mbuf *, tcp_seq, tcp_seq, int);
1060 void	 tcp_tw_init(void);
1061 #ifdef VIMAGE
1062 void	 tcp_tw_destroy(void);
1063 #endif
1064 void	 tcp_tw_zone_change(void);
1065 int	 tcp_twcheck(struct inpcb *, struct tcpopt *, struct tcphdr *,
1066 	    struct mbuf *, int);
1067 void	 tcp_setpersist(struct tcpcb *);
1068 void	 tcp_slowtimo(void);
1069 struct tcptemp *
1070 	 tcpip_maketemplate(struct inpcb *);
1071 void	 tcpip_fillheaders(struct inpcb *, uint16_t, void *, void *);
1072 void	 tcp_timer_activate(struct tcpcb *, uint32_t, u_int);
1073 int	 tcp_timer_suspend(struct tcpcb *, uint32_t);
1074 void	 tcp_timers_unsuspend(struct tcpcb *, uint32_t);
1075 int	 tcp_timer_active(struct tcpcb *, uint32_t);
1076 void	 tcp_timer_stop(struct tcpcb *, uint32_t);
1077 void	 tcp_trace(short, short, struct tcpcb *, void *, struct tcphdr *, int);
1078 int	 inp_to_cpuid(struct inpcb *inp);
1079 /*
1080  * All tcp_hc_* functions are IPv4 and IPv6 (via in_conninfo)
1081  */
1082 void	 tcp_hc_init(void);
1083 #ifdef VIMAGE
1084 void	 tcp_hc_destroy(void);
1085 #endif
1086 void	 tcp_hc_get(struct in_conninfo *, struct hc_metrics_lite *);
1087 uint32_t tcp_hc_getmtu(struct in_conninfo *);
1088 void	 tcp_hc_updatemtu(struct in_conninfo *, uint32_t);
1089 void	 tcp_hc_update(struct in_conninfo *, struct hc_metrics_lite *);
1090 
1091 extern	struct pr_usrreqs tcp_usrreqs;
1092 
1093 uint32_t tcp_new_ts_offset(struct in_conninfo *);
1094 tcp_seq	 tcp_new_isn(struct in_conninfo *);
1095 
1096 int	 tcp_sack_doack(struct tcpcb *, struct tcpopt *, tcp_seq);
1097 int	 tcp_dsack_block_exists(struct tcpcb *);
1098 void	 tcp_update_dsack_list(struct tcpcb *, tcp_seq, tcp_seq);
1099 void	 tcp_update_sack_list(struct tcpcb *tp, tcp_seq rcv_laststart, tcp_seq rcv_lastend);
1100 void	 tcp_clean_dsack_blocks(struct tcpcb *tp);
1101 void	 tcp_clean_sackreport(struct tcpcb *tp);
1102 void	 tcp_sack_adjust(struct tcpcb *tp);
1103 struct sackhole *tcp_sack_output(struct tcpcb *tp, int *sack_bytes_rexmt);
1104 void	 tcp_do_prr_ack(struct tcpcb *, struct tcphdr *, struct tcpopt *);
1105 void	 tcp_sack_partialack(struct tcpcb *, struct tcphdr *);
1106 void	 tcp_free_sackholes(struct tcpcb *tp);
1107 int	 tcp_newreno(struct tcpcb *, struct tcphdr *);
1108 int	 tcp_compute_pipe(struct tcpcb *);
1109 uint32_t tcp_compute_initwnd(uint32_t);
1110 void	 tcp_sndbuf_autoscale(struct tcpcb *, struct socket *, uint32_t);
1111 int	 tcp_stats_sample_rollthedice(struct tcpcb *tp, void *seed_bytes,
1112     size_t seed_len);
1113 int tcp_can_enable_pacing(void);
1114 void tcp_decrement_paced_conn(void);
1115 
1116 struct mbuf *
1117 	 tcp_m_copym(struct mbuf *m, int32_t off0, int32_t *plen,
1118 	   int32_t seglimit, int32_t segsize, struct sockbuf *sb, bool hw_tls);
1119 
1120 int	tcp_stats_init(void);
1121 void tcp_log_end_status(struct tcpcb *tp, uint8_t status);
1122 
1123 static inline void
tcp_fields_to_host(struct tcphdr * th)1124 tcp_fields_to_host(struct tcphdr *th)
1125 {
1126 
1127 	th->th_seq = ntohl(th->th_seq);
1128 	th->th_ack = ntohl(th->th_ack);
1129 	th->th_win = ntohs(th->th_win);
1130 	th->th_urp = ntohs(th->th_urp);
1131 }
1132 
1133 static inline void
tcp_fields_to_net(struct tcphdr * th)1134 tcp_fields_to_net(struct tcphdr *th)
1135 {
1136 
1137 	th->th_seq = htonl(th->th_seq);
1138 	th->th_ack = htonl(th->th_ack);
1139 	th->th_win = htons(th->th_win);
1140 	th->th_urp = htons(th->th_urp);
1141 }
1142 
1143 static inline void
tcp_account_for_send(struct tcpcb * tp,uint32_t len,uint8_t is_rxt,uint8_t is_tlp,int hw_tls __unused)1144 tcp_account_for_send(struct tcpcb *tp, uint32_t len, uint8_t is_rxt,
1145     uint8_t is_tlp, int hw_tls __unused)
1146 {
1147 	if (is_tlp) {
1148 		tp->t_sndtlppack++;
1149 		tp->t_sndtlpbyte += len;
1150 	}
1151 	/* To get total bytes sent you must add t_snd_rxt_bytes to t_sndbytes */
1152 	if (is_rxt)
1153 		tp->t_snd_rxt_bytes += len;
1154 	else
1155 		tp->t_sndbytes += len;
1156 }
1157 #endif /* _KERNEL */
1158 
1159 #endif /* _NETINET_TCP_VAR_H_ */
1160