xref: /freebsd/sys/netinet/tcp_usrreq.c (revision 74ca7bf1d4c7173d5575ba168bc4b5f6d181ff5a)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1982, 1986, 1988, 1993
5  *	The Regents of the University of California.
6  * Copyright (c) 2006-2007 Robert N. M. Watson
7  * Copyright (c) 2010-2011 Juniper Networks, Inc.
8  * All rights reserved.
9  *
10  * Portions of this software were developed by Robert N. M. Watson under
11  * contract to Juniper Networks, Inc.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  *
37  *	From: @(#)tcp_usrreq.c	8.2 (Berkeley) 1/3/94
38  */
39 
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
42 
43 #include "opt_ddb.h"
44 #include "opt_inet.h"
45 #include "opt_inet6.h"
46 #include "opt_ipsec.h"
47 #include "opt_tcpdebug.h"
48 
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/limits.h>
52 #include <sys/malloc.h>
53 #include <sys/refcount.h>
54 #include <sys/kernel.h>
55 #include <sys/sysctl.h>
56 #include <sys/mbuf.h>
57 #ifdef INET6
58 #include <sys/domain.h>
59 #endif /* INET6 */
60 #include <sys/socket.h>
61 #include <sys/socketvar.h>
62 #include <sys/protosw.h>
63 #include <sys/proc.h>
64 #include <sys/jail.h>
65 #include <sys/syslog.h>
66 
67 #ifdef DDB
68 #include <ddb/ddb.h>
69 #endif
70 
71 #include <net/if.h>
72 #include <net/if_var.h>
73 #include <net/route.h>
74 #include <net/vnet.h>
75 
76 #include <netinet/in.h>
77 #include <netinet/in_kdtrace.h>
78 #include <netinet/in_pcb.h>
79 #include <netinet/in_systm.h>
80 #include <netinet/in_var.h>
81 #include <netinet/ip_var.h>
82 #ifdef INET6
83 #include <netinet/ip6.h>
84 #include <netinet6/in6_pcb.h>
85 #include <netinet6/ip6_var.h>
86 #include <netinet6/scope6_var.h>
87 #endif
88 #include <netinet/tcp.h>
89 #include <netinet/tcp_fsm.h>
90 #include <netinet/tcp_seq.h>
91 #include <netinet/tcp_timer.h>
92 #include <netinet/tcp_var.h>
93 #include <netinet/tcp_log_buf.h>
94 #include <netinet/tcpip.h>
95 #include <netinet/cc/cc.h>
96 #include <netinet/tcp_fastopen.h>
97 #ifdef TCPPCAP
98 #include <netinet/tcp_pcap.h>
99 #endif
100 #ifdef TCPDEBUG
101 #include <netinet/tcp_debug.h>
102 #endif
103 #ifdef TCP_OFFLOAD
104 #include <netinet/tcp_offload.h>
105 #endif
106 #include <netipsec/ipsec_support.h>
107 
108 /*
109  * TCP protocol interface to socket abstraction.
110  */
111 static int	tcp_attach(struct socket *);
112 #ifdef INET
113 static int	tcp_connect(struct tcpcb *, struct sockaddr *,
114 		    struct thread *td);
115 #endif /* INET */
116 #ifdef INET6
117 static int	tcp6_connect(struct tcpcb *, struct sockaddr *,
118 		    struct thread *td);
119 #endif /* INET6 */
120 static void	tcp_disconnect(struct tcpcb *);
121 static void	tcp_usrclosed(struct tcpcb *);
122 static void	tcp_fill_info(struct tcpcb *, struct tcp_info *);
123 
124 #ifdef TCPDEBUG
125 #define	TCPDEBUG0	int ostate = 0
126 #define	TCPDEBUG1()	ostate = tp ? tp->t_state : 0
127 #define	TCPDEBUG2(req)	if (tp && (so->so_options & SO_DEBUG)) \
128 				tcp_trace(TA_USER, ostate, tp, 0, 0, req)
129 #else
130 #define	TCPDEBUG0
131 #define	TCPDEBUG1()
132 #define	TCPDEBUG2(req)
133 #endif
134 
135 /*
136  * TCP attaches to socket via pru_attach(), reserving space,
137  * and an internet control block.
138  */
139 static int
140 tcp_usr_attach(struct socket *so, int proto, struct thread *td)
141 {
142 	struct inpcb *inp;
143 	struct tcpcb *tp = NULL;
144 	int error;
145 	TCPDEBUG0;
146 
147 	inp = sotoinpcb(so);
148 	KASSERT(inp == NULL, ("tcp_usr_attach: inp != NULL"));
149 	TCPDEBUG1();
150 
151 	error = tcp_attach(so);
152 	if (error)
153 		goto out;
154 
155 	if ((so->so_options & SO_LINGER) && so->so_linger == 0)
156 		so->so_linger = TCP_LINGERTIME;
157 
158 	inp = sotoinpcb(so);
159 	tp = intotcpcb(inp);
160 out:
161 	TCPDEBUG2(PRU_ATTACH);
162 	TCP_PROBE2(debug__user, tp, PRU_ATTACH);
163 	return error;
164 }
165 
166 /*
167  * tcp_detach is called when the socket layer loses its final reference
168  * to the socket, be it a file descriptor reference, a reference from TCP,
169  * etc.  At this point, there is only one case in which we will keep around
170  * inpcb state: time wait.
171  *
172  * This function can probably be re-absorbed back into tcp_usr_detach() now
173  * that there is a single detach path.
174  */
175 static void
176 tcp_detach(struct socket *so, struct inpcb *inp)
177 {
178 	struct tcpcb *tp;
179 
180 	INP_INFO_LOCK_ASSERT(&V_tcbinfo);
181 	INP_WLOCK_ASSERT(inp);
182 
183 	KASSERT(so->so_pcb == inp, ("tcp_detach: so_pcb != inp"));
184 	KASSERT(inp->inp_socket == so, ("tcp_detach: inp_socket != so"));
185 
186 	tp = intotcpcb(inp);
187 
188 	if (inp->inp_flags & INP_TIMEWAIT) {
189 		/*
190 		 * There are two cases to handle: one in which the time wait
191 		 * state is being discarded (INP_DROPPED), and one in which
192 		 * this connection will remain in timewait.  In the former,
193 		 * it is time to discard all state (except tcptw, which has
194 		 * already been discarded by the timewait close code, which
195 		 * should be further up the call stack somewhere).  In the
196 		 * latter case, we detach from the socket, but leave the pcb
197 		 * present until timewait ends.
198 		 *
199 		 * XXXRW: Would it be cleaner to free the tcptw here?
200 		 *
201 		 * Astute question indeed, from twtcp perspective there are
202 		 * four cases to consider:
203 		 *
204 		 * #1 tcp_detach is called at tcptw creation time by
205 		 *  tcp_twstart, then do not discard the newly created tcptw
206 		 *  and leave inpcb present until timewait ends
207 		 * #2 tcp_detach is called at tcptw creation time by
208 		 *  tcp_twstart, but connection is local and tw will be
209 		 *  discarded immediately
210 		 * #3 tcp_detach is called at timewait end (or reuse) by
211 		 *  tcp_twclose, then the tcptw has already been discarded
212 		 *  (or reused) and inpcb is freed here
213 		 * #4 tcp_detach is called() after timewait ends (or reuse)
214 		 *  (e.g. by soclose), then tcptw has already been discarded
215 		 *  (or reused) and inpcb is freed here
216 		 *
217 		 *  In all three cases the tcptw should not be freed here.
218 		 */
219 		if (inp->inp_flags & INP_DROPPED) {
220 			in_pcbdetach(inp);
221 			if (__predict_true(tp == NULL)) {
222 				in_pcbfree(inp);
223 			} else {
224 				/*
225 				 * This case should not happen as in TIMEWAIT
226 				 * state the inp should not be destroyed before
227 				 * its tcptw.  If INVARIANTS is defined, panic.
228 				 */
229 #ifdef INVARIANTS
230 				panic("%s: Panic before an inp double-free: "
231 				    "INP_TIMEWAIT && INP_DROPPED && tp != NULL"
232 				    , __func__);
233 #else
234 				log(LOG_ERR, "%s: Avoid an inp double-free: "
235 				    "INP_TIMEWAIT && INP_DROPPED && tp != NULL"
236 				    , __func__);
237 #endif
238 				INP_WUNLOCK(inp);
239 			}
240 		} else {
241 			in_pcbdetach(inp);
242 			INP_WUNLOCK(inp);
243 		}
244 	} else {
245 		/*
246 		 * If the connection is not in timewait, we consider two
247 		 * two conditions: one in which no further processing is
248 		 * necessary (dropped || embryonic), and one in which TCP is
249 		 * not yet done, but no longer requires the socket, so the
250 		 * pcb will persist for the time being.
251 		 *
252 		 * XXXRW: Does the second case still occur?
253 		 */
254 		if (inp->inp_flags & INP_DROPPED ||
255 		    tp->t_state < TCPS_SYN_SENT) {
256 			tcp_discardcb(tp);
257 			in_pcbdetach(inp);
258 			in_pcbfree(inp);
259 		} else {
260 			in_pcbdetach(inp);
261 			INP_WUNLOCK(inp);
262 		}
263 	}
264 }
265 
266 /*
267  * pru_detach() detaches the TCP protocol from the socket.
268  * If the protocol state is non-embryonic, then can't
269  * do this directly: have to initiate a pru_disconnect(),
270  * which may finish later; embryonic TCB's can just
271  * be discarded here.
272  */
273 static void
274 tcp_usr_detach(struct socket *so)
275 {
276 	struct inpcb *inp;
277 	int rlock = 0;
278 
279 	inp = sotoinpcb(so);
280 	KASSERT(inp != NULL, ("tcp_usr_detach: inp == NULL"));
281 	if (!INP_INFO_WLOCKED(&V_tcbinfo)) {
282 		INP_INFO_RLOCK(&V_tcbinfo);
283 		rlock = 1;
284 	}
285 	INP_WLOCK(inp);
286 	KASSERT(inp->inp_socket != NULL,
287 	    ("tcp_usr_detach: inp_socket == NULL"));
288 	tcp_detach(so, inp);
289 	if (rlock)
290 		INP_INFO_RUNLOCK(&V_tcbinfo);
291 }
292 
293 #ifdef INET
294 /*
295  * Give the socket an address.
296  */
297 static int
298 tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
299 {
300 	int error = 0;
301 	struct inpcb *inp;
302 	struct tcpcb *tp = NULL;
303 	struct sockaddr_in *sinp;
304 
305 	sinp = (struct sockaddr_in *)nam;
306 	if (nam->sa_len != sizeof (*sinp))
307 		return (EINVAL);
308 	/*
309 	 * Must check for multicast addresses and disallow binding
310 	 * to them.
311 	 */
312 	if (sinp->sin_family == AF_INET &&
313 	    IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
314 		return (EAFNOSUPPORT);
315 
316 	TCPDEBUG0;
317 	inp = sotoinpcb(so);
318 	KASSERT(inp != NULL, ("tcp_usr_bind: inp == NULL"));
319 	INP_WLOCK(inp);
320 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
321 		error = EINVAL;
322 		goto out;
323 	}
324 	tp = intotcpcb(inp);
325 	TCPDEBUG1();
326 	INP_HASH_WLOCK(&V_tcbinfo);
327 	error = in_pcbbind(inp, nam, td->td_ucred);
328 	INP_HASH_WUNLOCK(&V_tcbinfo);
329 out:
330 	TCPDEBUG2(PRU_BIND);
331 	TCP_PROBE2(debug__user, tp, PRU_BIND);
332 	INP_WUNLOCK(inp);
333 
334 	return (error);
335 }
336 #endif /* INET */
337 
338 #ifdef INET6
339 static int
340 tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
341 {
342 	int error = 0;
343 	struct inpcb *inp;
344 	struct tcpcb *tp = NULL;
345 	struct sockaddr_in6 *sin6p;
346 
347 	sin6p = (struct sockaddr_in6 *)nam;
348 	if (nam->sa_len != sizeof (*sin6p))
349 		return (EINVAL);
350 	/*
351 	 * Must check for multicast addresses and disallow binding
352 	 * to them.
353 	 */
354 	if (sin6p->sin6_family == AF_INET6 &&
355 	    IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr))
356 		return (EAFNOSUPPORT);
357 
358 	TCPDEBUG0;
359 	inp = sotoinpcb(so);
360 	KASSERT(inp != NULL, ("tcp6_usr_bind: inp == NULL"));
361 	INP_WLOCK(inp);
362 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
363 		error = EINVAL;
364 		goto out;
365 	}
366 	tp = intotcpcb(inp);
367 	TCPDEBUG1();
368 	INP_HASH_WLOCK(&V_tcbinfo);
369 	inp->inp_vflag &= ~INP_IPV4;
370 	inp->inp_vflag |= INP_IPV6;
371 #ifdef INET
372 	if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
373 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6p->sin6_addr))
374 			inp->inp_vflag |= INP_IPV4;
375 		else if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
376 			struct sockaddr_in sin;
377 
378 			in6_sin6_2_sin(&sin, sin6p);
379 			inp->inp_vflag |= INP_IPV4;
380 			inp->inp_vflag &= ~INP_IPV6;
381 			error = in_pcbbind(inp, (struct sockaddr *)&sin,
382 			    td->td_ucred);
383 			INP_HASH_WUNLOCK(&V_tcbinfo);
384 			goto out;
385 		}
386 	}
387 #endif
388 	error = in6_pcbbind(inp, nam, td->td_ucred);
389 	INP_HASH_WUNLOCK(&V_tcbinfo);
390 out:
391 	TCPDEBUG2(PRU_BIND);
392 	TCP_PROBE2(debug__user, tp, PRU_BIND);
393 	INP_WUNLOCK(inp);
394 	return (error);
395 }
396 #endif /* INET6 */
397 
398 #ifdef INET
399 /*
400  * Prepare to accept connections.
401  */
402 static int
403 tcp_usr_listen(struct socket *so, int backlog, struct thread *td)
404 {
405 	int error = 0;
406 	struct inpcb *inp;
407 	struct tcpcb *tp = NULL;
408 
409 	TCPDEBUG0;
410 	inp = sotoinpcb(so);
411 	KASSERT(inp != NULL, ("tcp_usr_listen: inp == NULL"));
412 	INP_WLOCK(inp);
413 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
414 		error = EINVAL;
415 		goto out;
416 	}
417 	tp = intotcpcb(inp);
418 	TCPDEBUG1();
419 	SOCK_LOCK(so);
420 	error = solisten_proto_check(so);
421 	INP_HASH_WLOCK(&V_tcbinfo);
422 	if (error == 0 && inp->inp_lport == 0)
423 		error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
424 	INP_HASH_WUNLOCK(&V_tcbinfo);
425 	if (error == 0) {
426 		tcp_state_change(tp, TCPS_LISTEN);
427 		solisten_proto(so, backlog);
428 #ifdef TCP_OFFLOAD
429 		if ((so->so_options & SO_NO_OFFLOAD) == 0)
430 			tcp_offload_listen_start(tp);
431 #endif
432 	}
433 	SOCK_UNLOCK(so);
434 
435 	if (IS_FASTOPEN(tp->t_flags))
436 		tp->t_tfo_pending = tcp_fastopen_alloc_counter();
437 
438 out:
439 	TCPDEBUG2(PRU_LISTEN);
440 	TCP_PROBE2(debug__user, tp, PRU_LISTEN);
441 	INP_WUNLOCK(inp);
442 	return (error);
443 }
444 #endif /* INET */
445 
446 #ifdef INET6
447 static int
448 tcp6_usr_listen(struct socket *so, int backlog, struct thread *td)
449 {
450 	int error = 0;
451 	struct inpcb *inp;
452 	struct tcpcb *tp = NULL;
453 
454 	TCPDEBUG0;
455 	inp = sotoinpcb(so);
456 	KASSERT(inp != NULL, ("tcp6_usr_listen: inp == NULL"));
457 	INP_WLOCK(inp);
458 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
459 		error = EINVAL;
460 		goto out;
461 	}
462 	tp = intotcpcb(inp);
463 	TCPDEBUG1();
464 	SOCK_LOCK(so);
465 	error = solisten_proto_check(so);
466 	INP_HASH_WLOCK(&V_tcbinfo);
467 	if (error == 0 && inp->inp_lport == 0) {
468 		inp->inp_vflag &= ~INP_IPV4;
469 		if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
470 			inp->inp_vflag |= INP_IPV4;
471 		error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
472 	}
473 	INP_HASH_WUNLOCK(&V_tcbinfo);
474 	if (error == 0) {
475 		tcp_state_change(tp, TCPS_LISTEN);
476 		solisten_proto(so, backlog);
477 #ifdef TCP_OFFLOAD
478 		if ((so->so_options & SO_NO_OFFLOAD) == 0)
479 			tcp_offload_listen_start(tp);
480 #endif
481 	}
482 	SOCK_UNLOCK(so);
483 
484 	if (IS_FASTOPEN(tp->t_flags))
485 		tp->t_tfo_pending = tcp_fastopen_alloc_counter();
486 
487 out:
488 	TCPDEBUG2(PRU_LISTEN);
489 	TCP_PROBE2(debug__user, tp, PRU_LISTEN);
490 	INP_WUNLOCK(inp);
491 	return (error);
492 }
493 #endif /* INET6 */
494 
495 #ifdef INET
496 /*
497  * Initiate connection to peer.
498  * Create a template for use in transmissions on this connection.
499  * Enter SYN_SENT state, and mark socket as connecting.
500  * Start keep-alive timer, and seed output sequence space.
501  * Send initial segment on connection.
502  */
503 static int
504 tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
505 {
506 	int error = 0;
507 	struct inpcb *inp;
508 	struct tcpcb *tp = NULL;
509 	struct sockaddr_in *sinp;
510 
511 	sinp = (struct sockaddr_in *)nam;
512 	if (nam->sa_len != sizeof (*sinp))
513 		return (EINVAL);
514 	/*
515 	 * Must disallow TCP ``connections'' to multicast addresses.
516 	 */
517 	if (sinp->sin_family == AF_INET
518 	    && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
519 		return (EAFNOSUPPORT);
520 	if ((error = prison_remote_ip4(td->td_ucred, &sinp->sin_addr)) != 0)
521 		return (error);
522 
523 	TCPDEBUG0;
524 	inp = sotoinpcb(so);
525 	KASSERT(inp != NULL, ("tcp_usr_connect: inp == NULL"));
526 	INP_WLOCK(inp);
527 	if (inp->inp_flags & INP_TIMEWAIT) {
528 		error = EADDRINUSE;
529 		goto out;
530 	}
531 	if (inp->inp_flags & INP_DROPPED) {
532 		error = ECONNREFUSED;
533 		goto out;
534 	}
535 	tp = intotcpcb(inp);
536 	TCPDEBUG1();
537 	if ((error = tcp_connect(tp, nam, td)) != 0)
538 		goto out;
539 #ifdef TCP_OFFLOAD
540 	if (registered_toedevs > 0 &&
541 	    (so->so_options & SO_NO_OFFLOAD) == 0 &&
542 	    (error = tcp_offload_connect(so, nam)) == 0)
543 		goto out;
544 #endif
545 	tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
546 	error = tp->t_fb->tfb_tcp_output(tp);
547 out:
548 	TCPDEBUG2(PRU_CONNECT);
549 	TCP_PROBE2(debug__user, tp, PRU_CONNECT);
550 	INP_WUNLOCK(inp);
551 	return (error);
552 }
553 #endif /* INET */
554 
555 #ifdef INET6
556 static int
557 tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
558 {
559 	int error = 0;
560 	struct inpcb *inp;
561 	struct tcpcb *tp = NULL;
562 	struct sockaddr_in6 *sin6p;
563 
564 	TCPDEBUG0;
565 
566 	sin6p = (struct sockaddr_in6 *)nam;
567 	if (nam->sa_len != sizeof (*sin6p))
568 		return (EINVAL);
569 	/*
570 	 * Must disallow TCP ``connections'' to multicast addresses.
571 	 */
572 	if (sin6p->sin6_family == AF_INET6
573 	    && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr))
574 		return (EAFNOSUPPORT);
575 
576 	inp = sotoinpcb(so);
577 	KASSERT(inp != NULL, ("tcp6_usr_connect: inp == NULL"));
578 	INP_WLOCK(inp);
579 	if (inp->inp_flags & INP_TIMEWAIT) {
580 		error = EADDRINUSE;
581 		goto out;
582 	}
583 	if (inp->inp_flags & INP_DROPPED) {
584 		error = ECONNREFUSED;
585 		goto out;
586 	}
587 	tp = intotcpcb(inp);
588 	TCPDEBUG1();
589 #ifdef INET
590 	/*
591 	 * XXXRW: Some confusion: V4/V6 flags relate to binding, and
592 	 * therefore probably require the hash lock, which isn't held here.
593 	 * Is this a significant problem?
594 	 */
595 	if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
596 		struct sockaddr_in sin;
597 
598 		if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
599 			error = EINVAL;
600 			goto out;
601 		}
602 		if ((inp->inp_vflag & INP_IPV4) == 0) {
603 			error = EAFNOSUPPORT;
604 			goto out;
605 		}
606 
607 		in6_sin6_2_sin(&sin, sin6p);
608 		inp->inp_vflag |= INP_IPV4;
609 		inp->inp_vflag &= ~INP_IPV6;
610 		if ((error = prison_remote_ip4(td->td_ucred,
611 		    &sin.sin_addr)) != 0)
612 			goto out;
613 		if ((error = tcp_connect(tp, (struct sockaddr *)&sin, td)) != 0)
614 			goto out;
615 #ifdef TCP_OFFLOAD
616 		if (registered_toedevs > 0 &&
617 		    (so->so_options & SO_NO_OFFLOAD) == 0 &&
618 		    (error = tcp_offload_connect(so, nam)) == 0)
619 			goto out;
620 #endif
621 		error = tp->t_fb->tfb_tcp_output(tp);
622 		goto out;
623 	} else {
624 		if ((inp->inp_vflag & INP_IPV6) == 0) {
625 			error = EAFNOSUPPORT;
626 			goto out;
627 		}
628 	}
629 #endif
630 	inp->inp_vflag &= ~INP_IPV4;
631 	inp->inp_vflag |= INP_IPV6;
632 	inp->inp_inc.inc_flags |= INC_ISIPV6;
633 	if ((error = prison_remote_ip6(td->td_ucred, &sin6p->sin6_addr)) != 0)
634 		goto out;
635 	if ((error = tcp6_connect(tp, nam, td)) != 0)
636 		goto out;
637 #ifdef TCP_OFFLOAD
638 	if (registered_toedevs > 0 &&
639 	    (so->so_options & SO_NO_OFFLOAD) == 0 &&
640 	    (error = tcp_offload_connect(so, nam)) == 0)
641 		goto out;
642 #endif
643 	tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
644 	error = tp->t_fb->tfb_tcp_output(tp);
645 
646 out:
647 	TCPDEBUG2(PRU_CONNECT);
648 	TCP_PROBE2(debug__user, tp, PRU_CONNECT);
649 	INP_WUNLOCK(inp);
650 	return (error);
651 }
652 #endif /* INET6 */
653 
654 /*
655  * Initiate disconnect from peer.
656  * If connection never passed embryonic stage, just drop;
657  * else if don't need to let data drain, then can just drop anyways,
658  * else have to begin TCP shutdown process: mark socket disconnecting,
659  * drain unread data, state switch to reflect user close, and
660  * send segment (e.g. FIN) to peer.  Socket will be really disconnected
661  * when peer sends FIN and acks ours.
662  *
663  * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.
664  */
665 static int
666 tcp_usr_disconnect(struct socket *so)
667 {
668 	struct inpcb *inp;
669 	struct tcpcb *tp = NULL;
670 	int error = 0;
671 
672 	TCPDEBUG0;
673 	INP_INFO_RLOCK(&V_tcbinfo);
674 	inp = sotoinpcb(so);
675 	KASSERT(inp != NULL, ("tcp_usr_disconnect: inp == NULL"));
676 	INP_WLOCK(inp);
677 	if (inp->inp_flags & INP_TIMEWAIT)
678 		goto out;
679 	if (inp->inp_flags & INP_DROPPED) {
680 		error = ECONNRESET;
681 		goto out;
682 	}
683 	tp = intotcpcb(inp);
684 	TCPDEBUG1();
685 	tcp_disconnect(tp);
686 out:
687 	TCPDEBUG2(PRU_DISCONNECT);
688 	TCP_PROBE2(debug__user, tp, PRU_DISCONNECT);
689 	INP_WUNLOCK(inp);
690 	INP_INFO_RUNLOCK(&V_tcbinfo);
691 	return (error);
692 }
693 
694 #ifdef INET
695 /*
696  * Accept a connection.  Essentially all the work is done at higher levels;
697  * just return the address of the peer, storing through addr.
698  */
699 static int
700 tcp_usr_accept(struct socket *so, struct sockaddr **nam)
701 {
702 	int error = 0;
703 	struct inpcb *inp = NULL;
704 	struct tcpcb *tp = NULL;
705 	struct in_addr addr;
706 	in_port_t port = 0;
707 	TCPDEBUG0;
708 
709 	if (so->so_state & SS_ISDISCONNECTED)
710 		return (ECONNABORTED);
711 
712 	inp = sotoinpcb(so);
713 	KASSERT(inp != NULL, ("tcp_usr_accept: inp == NULL"));
714 	INP_WLOCK(inp);
715 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
716 		error = ECONNABORTED;
717 		goto out;
718 	}
719 	tp = intotcpcb(inp);
720 	TCPDEBUG1();
721 
722 	/*
723 	 * We inline in_getpeeraddr and COMMON_END here, so that we can
724 	 * copy the data of interest and defer the malloc until after we
725 	 * release the lock.
726 	 */
727 	port = inp->inp_fport;
728 	addr = inp->inp_faddr;
729 
730 out:
731 	TCPDEBUG2(PRU_ACCEPT);
732 	TCP_PROBE2(debug__user, tp, PRU_ACCEPT);
733 	INP_WUNLOCK(inp);
734 	if (error == 0)
735 		*nam = in_sockaddr(port, &addr);
736 	return error;
737 }
738 #endif /* INET */
739 
740 #ifdef INET6
741 static int
742 tcp6_usr_accept(struct socket *so, struct sockaddr **nam)
743 {
744 	struct inpcb *inp = NULL;
745 	int error = 0;
746 	struct tcpcb *tp = NULL;
747 	struct in_addr addr;
748 	struct in6_addr addr6;
749 	in_port_t port = 0;
750 	int v4 = 0;
751 	TCPDEBUG0;
752 
753 	if (so->so_state & SS_ISDISCONNECTED)
754 		return (ECONNABORTED);
755 
756 	inp = sotoinpcb(so);
757 	KASSERT(inp != NULL, ("tcp6_usr_accept: inp == NULL"));
758 	INP_INFO_RLOCK(&V_tcbinfo);
759 	INP_WLOCK(inp);
760 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
761 		error = ECONNABORTED;
762 		goto out;
763 	}
764 	tp = intotcpcb(inp);
765 	TCPDEBUG1();
766 
767 	/*
768 	 * We inline in6_mapped_peeraddr and COMMON_END here, so that we can
769 	 * copy the data of interest and defer the malloc until after we
770 	 * release the lock.
771 	 */
772 	if (inp->inp_vflag & INP_IPV4) {
773 		v4 = 1;
774 		port = inp->inp_fport;
775 		addr = inp->inp_faddr;
776 	} else {
777 		port = inp->inp_fport;
778 		addr6 = inp->in6p_faddr;
779 	}
780 
781 out:
782 	TCPDEBUG2(PRU_ACCEPT);
783 	TCP_PROBE2(debug__user, tp, PRU_ACCEPT);
784 	INP_WUNLOCK(inp);
785 	INP_INFO_RUNLOCK(&V_tcbinfo);
786 	if (error == 0) {
787 		if (v4)
788 			*nam = in6_v4mapsin6_sockaddr(port, &addr);
789 		else
790 			*nam = in6_sockaddr(port, &addr6);
791 	}
792 	return error;
793 }
794 #endif /* INET6 */
795 
796 /*
797  * Mark the connection as being incapable of further output.
798  */
799 static int
800 tcp_usr_shutdown(struct socket *so)
801 {
802 	int error = 0;
803 	struct inpcb *inp;
804 	struct tcpcb *tp = NULL;
805 
806 	TCPDEBUG0;
807 	INP_INFO_RLOCK(&V_tcbinfo);
808 	inp = sotoinpcb(so);
809 	KASSERT(inp != NULL, ("inp == NULL"));
810 	INP_WLOCK(inp);
811 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
812 		error = ECONNRESET;
813 		goto out;
814 	}
815 	tp = intotcpcb(inp);
816 	TCPDEBUG1();
817 	socantsendmore(so);
818 	tcp_usrclosed(tp);
819 	if (!(inp->inp_flags & INP_DROPPED))
820 		error = tp->t_fb->tfb_tcp_output(tp);
821 
822 out:
823 	TCPDEBUG2(PRU_SHUTDOWN);
824 	TCP_PROBE2(debug__user, tp, PRU_SHUTDOWN);
825 	INP_WUNLOCK(inp);
826 	INP_INFO_RUNLOCK(&V_tcbinfo);
827 
828 	return (error);
829 }
830 
831 /*
832  * After a receive, possibly send window update to peer.
833  */
834 static int
835 tcp_usr_rcvd(struct socket *so, int flags)
836 {
837 	struct inpcb *inp;
838 	struct tcpcb *tp = NULL;
839 	int error = 0;
840 
841 	TCPDEBUG0;
842 	inp = sotoinpcb(so);
843 	KASSERT(inp != NULL, ("tcp_usr_rcvd: inp == NULL"));
844 	INP_WLOCK(inp);
845 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
846 		error = ECONNRESET;
847 		goto out;
848 	}
849 	tp = intotcpcb(inp);
850 	TCPDEBUG1();
851 	/*
852 	 * For passively-created TFO connections, don't attempt a window
853 	 * update while still in SYN_RECEIVED as this may trigger an early
854 	 * SYN|ACK.  It is preferable to have the SYN|ACK be sent along with
855 	 * application response data, or failing that, when the DELACK timer
856 	 * expires.
857 	 */
858 	if (IS_FASTOPEN(tp->t_flags) &&
859 	    (tp->t_state == TCPS_SYN_RECEIVED))
860 		goto out;
861 #ifdef TCP_OFFLOAD
862 	if (tp->t_flags & TF_TOE)
863 		tcp_offload_rcvd(tp);
864 	else
865 #endif
866 	tp->t_fb->tfb_tcp_output(tp);
867 
868 out:
869 	TCPDEBUG2(PRU_RCVD);
870 	TCP_PROBE2(debug__user, tp, PRU_RCVD);
871 	INP_WUNLOCK(inp);
872 	return (error);
873 }
874 
875 /*
876  * Do a send by putting data in output queue and updating urgent
877  * marker if URG set.  Possibly send more data.  Unlike the other
878  * pru_*() routines, the mbuf chains are our responsibility.  We
879  * must either enqueue them or free them.  The other pru_* routines
880  * generally are caller-frees.
881  */
882 static int
883 tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
884     struct sockaddr *nam, struct mbuf *control, struct thread *td)
885 {
886 	int error = 0;
887 	struct inpcb *inp;
888 	struct tcpcb *tp = NULL;
889 #ifdef INET6
890 	int isipv6;
891 #endif
892 	TCPDEBUG0;
893 
894 	/*
895 	 * We require the pcbinfo lock if we will close the socket as part of
896 	 * this call.
897 	 */
898 	if (flags & PRUS_EOF)
899 		INP_INFO_RLOCK(&V_tcbinfo);
900 	inp = sotoinpcb(so);
901 	KASSERT(inp != NULL, ("tcp_usr_send: inp == NULL"));
902 	INP_WLOCK(inp);
903 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
904 		if (control)
905 			m_freem(control);
906 		/*
907 		 * In case of PRUS_NOTREADY, tcp_usr_ready() is responsible
908 		 * for freeing memory.
909 		 */
910 		if (m && (flags & PRUS_NOTREADY) == 0)
911 			m_freem(m);
912 		error = ECONNRESET;
913 		goto out;
914 	}
915 #ifdef INET6
916 	isipv6 = nam && nam->sa_family == AF_INET6;
917 #endif /* INET6 */
918 	tp = intotcpcb(inp);
919 	TCPDEBUG1();
920 	if (control) {
921 		/* TCP doesn't do control messages (rights, creds, etc) */
922 		if (control->m_len) {
923 			m_freem(control);
924 			if (m)
925 				m_freem(m);
926 			error = EINVAL;
927 			goto out;
928 		}
929 		m_freem(control);	/* empty control, just free it */
930 	}
931 	if (!(flags & PRUS_OOB)) {
932 		sbappendstream(&so->so_snd, m, flags);
933 		if (nam && tp->t_state < TCPS_SYN_SENT) {
934 			/*
935 			 * Do implied connect if not yet connected,
936 			 * initialize window to default value, and
937 			 * initialize maxseg using peer's cached MSS.
938 			 */
939 #ifdef INET6
940 			if (isipv6)
941 				error = tcp6_connect(tp, nam, td);
942 #endif /* INET6 */
943 #if defined(INET6) && defined(INET)
944 			else
945 #endif
946 #ifdef INET
947 				error = tcp_connect(tp, nam, td);
948 #endif
949 			if (error)
950 				goto out;
951 			if (IS_FASTOPEN(tp->t_flags))
952 				tcp_fastopen_connect(tp);
953 			else {
954 				tp->snd_wnd = TTCP_CLIENT_SND_WND;
955 				tcp_mss(tp, -1);
956 			}
957 		}
958 		if (flags & PRUS_EOF) {
959 			/*
960 			 * Close the send side of the connection after
961 			 * the data is sent.
962 			 */
963 			INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
964 			socantsendmore(so);
965 			tcp_usrclosed(tp);
966 		}
967 		if (!(inp->inp_flags & INP_DROPPED) &&
968 		    !(flags & PRUS_NOTREADY)) {
969 			if (flags & PRUS_MORETOCOME)
970 				tp->t_flags |= TF_MORETOCOME;
971 			error = tp->t_fb->tfb_tcp_output(tp);
972 			if (flags & PRUS_MORETOCOME)
973 				tp->t_flags &= ~TF_MORETOCOME;
974 		}
975 	} else {
976 		/*
977 		 * XXXRW: PRUS_EOF not implemented with PRUS_OOB?
978 		 */
979 		SOCKBUF_LOCK(&so->so_snd);
980 		if (sbspace(&so->so_snd) < -512) {
981 			SOCKBUF_UNLOCK(&so->so_snd);
982 			m_freem(m);
983 			error = ENOBUFS;
984 			goto out;
985 		}
986 		/*
987 		 * According to RFC961 (Assigned Protocols),
988 		 * the urgent pointer points to the last octet
989 		 * of urgent data.  We continue, however,
990 		 * to consider it to indicate the first octet
991 		 * of data past the urgent section.
992 		 * Otherwise, snd_up should be one lower.
993 		 */
994 		sbappendstream_locked(&so->so_snd, m, flags);
995 		SOCKBUF_UNLOCK(&so->so_snd);
996 		if (nam && tp->t_state < TCPS_SYN_SENT) {
997 			/*
998 			 * Do implied connect if not yet connected,
999 			 * initialize window to default value, and
1000 			 * initialize maxseg using peer's cached MSS.
1001 			 */
1002 
1003 			/*
1004 			 * Not going to contemplate SYN|URG
1005 			 */
1006 			if (IS_FASTOPEN(tp->t_flags))
1007 				tp->t_flags &= ~TF_FASTOPEN;
1008 #ifdef INET6
1009 			if (isipv6)
1010 				error = tcp6_connect(tp, nam, td);
1011 #endif /* INET6 */
1012 #if defined(INET6) && defined(INET)
1013 			else
1014 #endif
1015 #ifdef INET
1016 				error = tcp_connect(tp, nam, td);
1017 #endif
1018 			if (error)
1019 				goto out;
1020 			tp->snd_wnd = TTCP_CLIENT_SND_WND;
1021 			tcp_mss(tp, -1);
1022 		}
1023 		tp->snd_up = tp->snd_una + sbavail(&so->so_snd);
1024 		if (!(flags & PRUS_NOTREADY)) {
1025 			tp->t_flags |= TF_FORCEDATA;
1026 			error = tp->t_fb->tfb_tcp_output(tp);
1027 			tp->t_flags &= ~TF_FORCEDATA;
1028 		}
1029 	}
1030 	TCP_LOG_EVENT(tp, NULL,
1031 	    &inp->inp_socket->so_rcv,
1032 	    &inp->inp_socket->so_snd,
1033 	    TCP_LOG_USERSEND, error,
1034 	    0, NULL, false);
1035 out:
1036 	TCPDEBUG2((flags & PRUS_OOB) ? PRU_SENDOOB :
1037 		  ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
1038 	TCP_PROBE2(debug__user, tp, (flags & PRUS_OOB) ? PRU_SENDOOB :
1039 		   ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
1040 	INP_WUNLOCK(inp);
1041 	if (flags & PRUS_EOF)
1042 		INP_INFO_RUNLOCK(&V_tcbinfo);
1043 	return (error);
1044 }
1045 
1046 static int
1047 tcp_usr_ready(struct socket *so, struct mbuf *m, int count)
1048 {
1049 	struct inpcb *inp;
1050 	struct tcpcb *tp;
1051 	int error;
1052 
1053 	inp = sotoinpcb(so);
1054 	INP_WLOCK(inp);
1055 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1056 		INP_WUNLOCK(inp);
1057 		for (int i = 0; i < count; i++)
1058 			m = m_free(m);
1059 		return (ECONNRESET);
1060 	}
1061 	tp = intotcpcb(inp);
1062 
1063 	SOCKBUF_LOCK(&so->so_snd);
1064 	error = sbready(&so->so_snd, m, count);
1065 	SOCKBUF_UNLOCK(&so->so_snd);
1066 	if (error == 0)
1067 		error = tp->t_fb->tfb_tcp_output(tp);
1068 	INP_WUNLOCK(inp);
1069 
1070 	return (error);
1071 }
1072 
1073 /*
1074  * Abort the TCP.  Drop the connection abruptly.
1075  */
1076 static void
1077 tcp_usr_abort(struct socket *so)
1078 {
1079 	struct inpcb *inp;
1080 	struct tcpcb *tp = NULL;
1081 	TCPDEBUG0;
1082 
1083 	inp = sotoinpcb(so);
1084 	KASSERT(inp != NULL, ("tcp_usr_abort: inp == NULL"));
1085 
1086 	INP_INFO_RLOCK(&V_tcbinfo);
1087 	INP_WLOCK(inp);
1088 	KASSERT(inp->inp_socket != NULL,
1089 	    ("tcp_usr_abort: inp_socket == NULL"));
1090 
1091 	/*
1092 	 * If we still have full TCP state, and we're not dropped, drop.
1093 	 */
1094 	if (!(inp->inp_flags & INP_TIMEWAIT) &&
1095 	    !(inp->inp_flags & INP_DROPPED)) {
1096 		tp = intotcpcb(inp);
1097 		TCPDEBUG1();
1098 		tcp_drop(tp, ECONNABORTED);
1099 		TCPDEBUG2(PRU_ABORT);
1100 		TCP_PROBE2(debug__user, tp, PRU_ABORT);
1101 	}
1102 	if (!(inp->inp_flags & INP_DROPPED)) {
1103 		SOCK_LOCK(so);
1104 		so->so_state |= SS_PROTOREF;
1105 		SOCK_UNLOCK(so);
1106 		inp->inp_flags |= INP_SOCKREF;
1107 	}
1108 	INP_WUNLOCK(inp);
1109 	INP_INFO_RUNLOCK(&V_tcbinfo);
1110 }
1111 
1112 /*
1113  * TCP socket is closed.  Start friendly disconnect.
1114  */
1115 static void
1116 tcp_usr_close(struct socket *so)
1117 {
1118 	struct inpcb *inp;
1119 	struct tcpcb *tp = NULL;
1120 	TCPDEBUG0;
1121 
1122 	inp = sotoinpcb(so);
1123 	KASSERT(inp != NULL, ("tcp_usr_close: inp == NULL"));
1124 
1125 	INP_INFO_RLOCK(&V_tcbinfo);
1126 	INP_WLOCK(inp);
1127 	KASSERT(inp->inp_socket != NULL,
1128 	    ("tcp_usr_close: inp_socket == NULL"));
1129 
1130 	/*
1131 	 * If we still have full TCP state, and we're not dropped, initiate
1132 	 * a disconnect.
1133 	 */
1134 	if (!(inp->inp_flags & INP_TIMEWAIT) &&
1135 	    !(inp->inp_flags & INP_DROPPED)) {
1136 		tp = intotcpcb(inp);
1137 		TCPDEBUG1();
1138 		tcp_disconnect(tp);
1139 		TCPDEBUG2(PRU_CLOSE);
1140 		TCP_PROBE2(debug__user, tp, PRU_CLOSE);
1141 	}
1142 	if (!(inp->inp_flags & INP_DROPPED)) {
1143 		SOCK_LOCK(so);
1144 		so->so_state |= SS_PROTOREF;
1145 		SOCK_UNLOCK(so);
1146 		inp->inp_flags |= INP_SOCKREF;
1147 	}
1148 	INP_WUNLOCK(inp);
1149 	INP_INFO_RUNLOCK(&V_tcbinfo);
1150 }
1151 
1152 /*
1153  * Receive out-of-band data.
1154  */
1155 static int
1156 tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags)
1157 {
1158 	int error = 0;
1159 	struct inpcb *inp;
1160 	struct tcpcb *tp = NULL;
1161 
1162 	TCPDEBUG0;
1163 	inp = sotoinpcb(so);
1164 	KASSERT(inp != NULL, ("tcp_usr_rcvoob: inp == NULL"));
1165 	INP_WLOCK(inp);
1166 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1167 		error = ECONNRESET;
1168 		goto out;
1169 	}
1170 	tp = intotcpcb(inp);
1171 	TCPDEBUG1();
1172 	if ((so->so_oobmark == 0 &&
1173 	     (so->so_rcv.sb_state & SBS_RCVATMARK) == 0) ||
1174 	    so->so_options & SO_OOBINLINE ||
1175 	    tp->t_oobflags & TCPOOB_HADDATA) {
1176 		error = EINVAL;
1177 		goto out;
1178 	}
1179 	if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
1180 		error = EWOULDBLOCK;
1181 		goto out;
1182 	}
1183 	m->m_len = 1;
1184 	*mtod(m, caddr_t) = tp->t_iobc;
1185 	if ((flags & MSG_PEEK) == 0)
1186 		tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
1187 
1188 out:
1189 	TCPDEBUG2(PRU_RCVOOB);
1190 	TCP_PROBE2(debug__user, tp, PRU_RCVOOB);
1191 	INP_WUNLOCK(inp);
1192 	return (error);
1193 }
1194 
1195 #ifdef INET
1196 struct pr_usrreqs tcp_usrreqs = {
1197 	.pru_abort =		tcp_usr_abort,
1198 	.pru_accept =		tcp_usr_accept,
1199 	.pru_attach =		tcp_usr_attach,
1200 	.pru_bind =		tcp_usr_bind,
1201 	.pru_connect =		tcp_usr_connect,
1202 	.pru_control =		in_control,
1203 	.pru_detach =		tcp_usr_detach,
1204 	.pru_disconnect =	tcp_usr_disconnect,
1205 	.pru_listen =		tcp_usr_listen,
1206 	.pru_peeraddr =		in_getpeeraddr,
1207 	.pru_rcvd =		tcp_usr_rcvd,
1208 	.pru_rcvoob =		tcp_usr_rcvoob,
1209 	.pru_send =		tcp_usr_send,
1210 	.pru_ready =		tcp_usr_ready,
1211 	.pru_shutdown =		tcp_usr_shutdown,
1212 	.pru_sockaddr =		in_getsockaddr,
1213 	.pru_sosetlabel =	in_pcbsosetlabel,
1214 	.pru_close =		tcp_usr_close,
1215 };
1216 #endif /* INET */
1217 
1218 #ifdef INET6
1219 struct pr_usrreqs tcp6_usrreqs = {
1220 	.pru_abort =		tcp_usr_abort,
1221 	.pru_accept =		tcp6_usr_accept,
1222 	.pru_attach =		tcp_usr_attach,
1223 	.pru_bind =		tcp6_usr_bind,
1224 	.pru_connect =		tcp6_usr_connect,
1225 	.pru_control =		in6_control,
1226 	.pru_detach =		tcp_usr_detach,
1227 	.pru_disconnect =	tcp_usr_disconnect,
1228 	.pru_listen =		tcp6_usr_listen,
1229 	.pru_peeraddr =		in6_mapped_peeraddr,
1230 	.pru_rcvd =		tcp_usr_rcvd,
1231 	.pru_rcvoob =		tcp_usr_rcvoob,
1232 	.pru_send =		tcp_usr_send,
1233 	.pru_ready =		tcp_usr_ready,
1234 	.pru_shutdown =		tcp_usr_shutdown,
1235 	.pru_sockaddr =		in6_mapped_sockaddr,
1236 	.pru_sosetlabel =	in_pcbsosetlabel,
1237 	.pru_close =		tcp_usr_close,
1238 };
1239 #endif /* INET6 */
1240 
1241 #ifdef INET
1242 /*
1243  * Common subroutine to open a TCP connection to remote host specified
1244  * by struct sockaddr_in in mbuf *nam.  Call in_pcbbind to assign a local
1245  * port number if needed.  Call in_pcbconnect_setup to do the routing and
1246  * to choose a local host address (interface).  If there is an existing
1247  * incarnation of the same connection in TIME-WAIT state and if the remote
1248  * host was sending CC options and if the connection duration was < MSL, then
1249  * truncate the previous TIME-WAIT state and proceed.
1250  * Initialize connection parameters and enter SYN-SENT state.
1251  */
1252 static int
1253 tcp_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1254 {
1255 	struct inpcb *inp = tp->t_inpcb, *oinp;
1256 	struct socket *so = inp->inp_socket;
1257 	struct in_addr laddr;
1258 	u_short lport;
1259 	int error;
1260 
1261 	INP_WLOCK_ASSERT(inp);
1262 	INP_HASH_WLOCK(&V_tcbinfo);
1263 
1264 	if (inp->inp_lport == 0) {
1265 		error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1266 		if (error)
1267 			goto out;
1268 	}
1269 
1270 	/*
1271 	 * Cannot simply call in_pcbconnect, because there might be an
1272 	 * earlier incarnation of this same connection still in
1273 	 * TIME_WAIT state, creating an ADDRINUSE error.
1274 	 */
1275 	laddr = inp->inp_laddr;
1276 	lport = inp->inp_lport;
1277 	error = in_pcbconnect_setup(inp, nam, &laddr.s_addr, &lport,
1278 	    &inp->inp_faddr.s_addr, &inp->inp_fport, &oinp, td->td_ucred);
1279 	if (error && oinp == NULL)
1280 		goto out;
1281 	if (oinp) {
1282 		error = EADDRINUSE;
1283 		goto out;
1284 	}
1285 	inp->inp_laddr = laddr;
1286 	in_pcbrehash(inp);
1287 	INP_HASH_WUNLOCK(&V_tcbinfo);
1288 
1289 	/*
1290 	 * Compute window scaling to request:
1291 	 * Scale to fit into sweet spot.  See tcp_syncache.c.
1292 	 * XXX: This should move to tcp_output().
1293 	 */
1294 	while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1295 	    (TCP_MAXWIN << tp->request_r_scale) < sb_max)
1296 		tp->request_r_scale++;
1297 
1298 	soisconnecting(so);
1299 	TCPSTAT_INC(tcps_connattempt);
1300 	tcp_state_change(tp, TCPS_SYN_SENT);
1301 	tp->iss = tcp_new_isn(tp);
1302 	tcp_sendseqinit(tp);
1303 
1304 	return 0;
1305 
1306 out:
1307 	INP_HASH_WUNLOCK(&V_tcbinfo);
1308 	return (error);
1309 }
1310 #endif /* INET */
1311 
1312 #ifdef INET6
1313 static int
1314 tcp6_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1315 {
1316 	struct inpcb *inp = tp->t_inpcb;
1317 	int error;
1318 
1319 	INP_WLOCK_ASSERT(inp);
1320 	INP_HASH_WLOCK(&V_tcbinfo);
1321 
1322 	if (inp->inp_lport == 0) {
1323 		error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1324 		if (error)
1325 			goto out;
1326 	}
1327 	error = in6_pcbconnect(inp, nam, td->td_ucred);
1328 	if (error != 0)
1329 		goto out;
1330 	INP_HASH_WUNLOCK(&V_tcbinfo);
1331 
1332 	/* Compute window scaling to request.  */
1333 	while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1334 	    (TCP_MAXWIN << tp->request_r_scale) < sb_max)
1335 		tp->request_r_scale++;
1336 
1337 	soisconnecting(inp->inp_socket);
1338 	TCPSTAT_INC(tcps_connattempt);
1339 	tcp_state_change(tp, TCPS_SYN_SENT);
1340 	tp->iss = tcp_new_isn(tp);
1341 	tcp_sendseqinit(tp);
1342 
1343 	return 0;
1344 
1345 out:
1346 	INP_HASH_WUNLOCK(&V_tcbinfo);
1347 	return error;
1348 }
1349 #endif /* INET6 */
1350 
1351 /*
1352  * Export TCP internal state information via a struct tcp_info, based on the
1353  * Linux 2.6 API.  Not ABI compatible as our constants are mapped differently
1354  * (TCP state machine, etc).  We export all information using FreeBSD-native
1355  * constants -- for example, the numeric values for tcpi_state will differ
1356  * from Linux.
1357  */
1358 static void
1359 tcp_fill_info(struct tcpcb *tp, struct tcp_info *ti)
1360 {
1361 
1362 	INP_WLOCK_ASSERT(tp->t_inpcb);
1363 	bzero(ti, sizeof(*ti));
1364 
1365 	ti->tcpi_state = tp->t_state;
1366 	if ((tp->t_flags & TF_REQ_TSTMP) && (tp->t_flags & TF_RCVD_TSTMP))
1367 		ti->tcpi_options |= TCPI_OPT_TIMESTAMPS;
1368 	if (tp->t_flags & TF_SACK_PERMIT)
1369 		ti->tcpi_options |= TCPI_OPT_SACK;
1370 	if ((tp->t_flags & TF_REQ_SCALE) && (tp->t_flags & TF_RCVD_SCALE)) {
1371 		ti->tcpi_options |= TCPI_OPT_WSCALE;
1372 		ti->tcpi_snd_wscale = tp->snd_scale;
1373 		ti->tcpi_rcv_wscale = tp->rcv_scale;
1374 	}
1375 	if (tp->t_flags & TF_ECN_PERMIT)
1376 		ti->tcpi_options |= TCPI_OPT_ECN;
1377 
1378 	ti->tcpi_rto = tp->t_rxtcur * tick;
1379 	ti->tcpi_last_data_recv = ((uint32_t)ticks - tp->t_rcvtime) * tick;
1380 	ti->tcpi_rtt = ((u_int64_t)tp->t_srtt * tick) >> TCP_RTT_SHIFT;
1381 	ti->tcpi_rttvar = ((u_int64_t)tp->t_rttvar * tick) >> TCP_RTTVAR_SHIFT;
1382 
1383 	ti->tcpi_snd_ssthresh = tp->snd_ssthresh;
1384 	ti->tcpi_snd_cwnd = tp->snd_cwnd;
1385 
1386 	/*
1387 	 * FreeBSD-specific extension fields for tcp_info.
1388 	 */
1389 	ti->tcpi_rcv_space = tp->rcv_wnd;
1390 	ti->tcpi_rcv_nxt = tp->rcv_nxt;
1391 	ti->tcpi_snd_wnd = tp->snd_wnd;
1392 	ti->tcpi_snd_bwnd = 0;		/* Unused, kept for compat. */
1393 	ti->tcpi_snd_nxt = tp->snd_nxt;
1394 	ti->tcpi_snd_mss = tp->t_maxseg;
1395 	ti->tcpi_rcv_mss = tp->t_maxseg;
1396 	if (tp->t_flags & TF_TOE)
1397 		ti->tcpi_options |= TCPI_OPT_TOE;
1398 	ti->tcpi_snd_rexmitpack = tp->t_sndrexmitpack;
1399 	ti->tcpi_rcv_ooopack = tp->t_rcvoopack;
1400 	ti->tcpi_snd_zerowin = tp->t_sndzerowin;
1401 }
1402 
1403 /*
1404  * tcp_ctloutput() must drop the inpcb lock before performing copyin on
1405  * socket option arguments.  When it re-acquires the lock after the copy, it
1406  * has to revalidate that the connection is still valid for the socket
1407  * option.
1408  */
1409 #define INP_WLOCK_RECHECK_CLEANUP(inp, cleanup) do {			\
1410 	INP_WLOCK(inp);							\
1411 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {		\
1412 		INP_WUNLOCK(inp);					\
1413 		cleanup;						\
1414 		return (ECONNRESET);					\
1415 	}								\
1416 	tp = intotcpcb(inp);						\
1417 } while(0)
1418 #define INP_WLOCK_RECHECK(inp) INP_WLOCK_RECHECK_CLEANUP((inp), /* noop */)
1419 
1420 int
1421 tcp_ctloutput(struct socket *so, struct sockopt *sopt)
1422 {
1423 	int	error;
1424 	struct	inpcb *inp;
1425 	struct	tcpcb *tp;
1426 	struct tcp_function_block *blk;
1427 	struct tcp_function_set fsn;
1428 
1429 	error = 0;
1430 	inp = sotoinpcb(so);
1431 	KASSERT(inp != NULL, ("tcp_ctloutput: inp == NULL"));
1432 	INP_WLOCK(inp);
1433 	if (sopt->sopt_level != IPPROTO_TCP) {
1434 #ifdef INET6
1435 		if (inp->inp_vflag & INP_IPV6PROTO) {
1436 			INP_WUNLOCK(inp);
1437 			error = ip6_ctloutput(so, sopt);
1438 		}
1439 #endif /* INET6 */
1440 #if defined(INET6) && defined(INET)
1441 		else
1442 #endif
1443 #ifdef INET
1444 		{
1445 			INP_WUNLOCK(inp);
1446 			error = ip_ctloutput(so, sopt);
1447 		}
1448 #endif
1449 		return (error);
1450 	}
1451 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1452 		INP_WUNLOCK(inp);
1453 		return (ECONNRESET);
1454 	}
1455 	tp = intotcpcb(inp);
1456 	/*
1457 	 * Protect the TCP option TCP_FUNCTION_BLK so
1458 	 * that a sub-function can *never* overwrite this.
1459 	 */
1460 	if ((sopt->sopt_dir == SOPT_SET) &&
1461 	    (sopt->sopt_name == TCP_FUNCTION_BLK)) {
1462 		INP_WUNLOCK(inp);
1463 		error = sooptcopyin(sopt, &fsn, sizeof fsn,
1464 		    sizeof fsn);
1465 		if (error)
1466 			return (error);
1467 		INP_WLOCK_RECHECK(inp);
1468 		blk = find_and_ref_tcp_functions(&fsn);
1469 		if (blk == NULL) {
1470 			INP_WUNLOCK(inp);
1471 			return (ENOENT);
1472 		}
1473 		if (tp->t_fb == blk) {
1474 			/* You already have this */
1475 			refcount_release(&blk->tfb_refcnt);
1476 			INP_WUNLOCK(inp);
1477 			return (0);
1478 		}
1479 		if (tp->t_state != TCPS_CLOSED) {
1480 			int error=EINVAL;
1481 			/*
1482 			 * The user has advanced the state
1483 			 * past the initial point, we may not
1484 			 * be able to switch.
1485 			 */
1486 			if (blk->tfb_tcp_handoff_ok != NULL) {
1487 				/*
1488 				 * Does the stack provide a
1489 				 * query mechanism, if so it may
1490 				 * still be possible?
1491 				 */
1492 				error = (*blk->tfb_tcp_handoff_ok)(tp);
1493 			}
1494 			if (error) {
1495 				refcount_release(&blk->tfb_refcnt);
1496 				INP_WUNLOCK(inp);
1497 				return(error);
1498 			}
1499 		}
1500 		if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) {
1501 			refcount_release(&blk->tfb_refcnt);
1502 			INP_WUNLOCK(inp);
1503 			return (ENOENT);
1504 		}
1505 		/*
1506 		 * Release the old refcnt, the
1507 		 * lookup acquired a ref on the
1508 		 * new one already.
1509 		 */
1510 		if (tp->t_fb->tfb_tcp_fb_fini) {
1511 			/*
1512 			 * Tell the stack to cleanup with 0 i.e.
1513 			 * the tcb is not going away.
1514 			 */
1515 			(*tp->t_fb->tfb_tcp_fb_fini)(tp, 0);
1516 		}
1517 		refcount_release(&tp->t_fb->tfb_refcnt);
1518 		tp->t_fb = blk;
1519 		if (tp->t_fb->tfb_tcp_fb_init) {
1520 			(*tp->t_fb->tfb_tcp_fb_init)(tp);
1521 		}
1522 #ifdef TCP_OFFLOAD
1523 		if (tp->t_flags & TF_TOE) {
1524 			tcp_offload_ctloutput(tp, sopt->sopt_dir,
1525 			     sopt->sopt_name);
1526 		}
1527 #endif
1528 		INP_WUNLOCK(inp);
1529 		return (error);
1530 	} else if ((sopt->sopt_dir == SOPT_GET) &&
1531 	    (sopt->sopt_name == TCP_FUNCTION_BLK)) {
1532 		strcpy(fsn.function_set_name, tp->t_fb->tfb_tcp_block_name);
1533 		fsn.pcbcnt = tp->t_fb->tfb_refcnt;
1534 		INP_WUNLOCK(inp);
1535 		error = sooptcopyout(sopt, &fsn, sizeof fsn);
1536 		return (error);
1537 	}
1538 	/* Pass in the INP locked, called must unlock it */
1539 	return (tp->t_fb->tfb_tcp_ctloutput(so, sopt, inp, tp));
1540 }
1541 
1542 /*
1543  * If this assert becomes untrue, we need to change the size of the buf
1544  * variable in tcp_default_ctloutput().
1545  */
1546 #ifdef CTASSERT
1547 CTASSERT(TCP_CA_NAME_MAX <= TCP_LOG_ID_LEN);
1548 CTASSERT(TCP_LOG_REASON_LEN <= TCP_LOG_ID_LEN);
1549 #endif
1550 
1551 int
1552 tcp_default_ctloutput(struct socket *so, struct sockopt *sopt, struct inpcb *inp, struct tcpcb *tp)
1553 {
1554 	int	error, opt, optval;
1555 	u_int	ui;
1556 	struct	tcp_info ti;
1557 	struct cc_algo *algo;
1558 	char	*pbuf, buf[TCP_LOG_ID_LEN];
1559 	size_t	len;
1560 
1561 	/*
1562 	 * For TCP_CCALGOOPT forward the control to CC module, for both
1563 	 * SOPT_SET and SOPT_GET.
1564 	 */
1565 	switch (sopt->sopt_name) {
1566 	case TCP_CCALGOOPT:
1567 		INP_WUNLOCK(inp);
1568 		pbuf = malloc(sopt->sopt_valsize, M_TEMP, M_WAITOK | M_ZERO);
1569 		error = sooptcopyin(sopt, pbuf, sopt->sopt_valsize,
1570 		    sopt->sopt_valsize);
1571 		if (error) {
1572 			free(pbuf, M_TEMP);
1573 			return (error);
1574 		}
1575 		INP_WLOCK_RECHECK_CLEANUP(inp, free(pbuf, M_TEMP));
1576 		if (CC_ALGO(tp)->ctl_output != NULL)
1577 			error = CC_ALGO(tp)->ctl_output(tp->ccv, sopt, pbuf);
1578 		else
1579 			error = ENOENT;
1580 		INP_WUNLOCK(inp);
1581 		if (error == 0 && sopt->sopt_dir == SOPT_GET)
1582 			error = sooptcopyout(sopt, pbuf, sopt->sopt_valsize);
1583 		free(pbuf, M_TEMP);
1584 		return (error);
1585 	}
1586 
1587 	switch (sopt->sopt_dir) {
1588 	case SOPT_SET:
1589 		switch (sopt->sopt_name) {
1590 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
1591 		case TCP_MD5SIG:
1592 			if (!TCPMD5_ENABLED()) {
1593 				INP_WUNLOCK(inp);
1594 				return (ENOPROTOOPT);
1595 			}
1596 			error = TCPMD5_PCBCTL(inp, sopt);
1597 			if (error)
1598 				return (error);
1599 			goto unlock_and_done;
1600 #endif /* IPSEC */
1601 
1602 		case TCP_NODELAY:
1603 		case TCP_NOOPT:
1604 			INP_WUNLOCK(inp);
1605 			error = sooptcopyin(sopt, &optval, sizeof optval,
1606 			    sizeof optval);
1607 			if (error)
1608 				return (error);
1609 
1610 			INP_WLOCK_RECHECK(inp);
1611 			switch (sopt->sopt_name) {
1612 			case TCP_NODELAY:
1613 				opt = TF_NODELAY;
1614 				break;
1615 			case TCP_NOOPT:
1616 				opt = TF_NOOPT;
1617 				break;
1618 			default:
1619 				opt = 0; /* dead code to fool gcc */
1620 				break;
1621 			}
1622 
1623 			if (optval)
1624 				tp->t_flags |= opt;
1625 			else
1626 				tp->t_flags &= ~opt;
1627 unlock_and_done:
1628 #ifdef TCP_OFFLOAD
1629 			if (tp->t_flags & TF_TOE) {
1630 				tcp_offload_ctloutput(tp, sopt->sopt_dir,
1631 				    sopt->sopt_name);
1632 			}
1633 #endif
1634 			INP_WUNLOCK(inp);
1635 			break;
1636 
1637 		case TCP_NOPUSH:
1638 			INP_WUNLOCK(inp);
1639 			error = sooptcopyin(sopt, &optval, sizeof optval,
1640 			    sizeof optval);
1641 			if (error)
1642 				return (error);
1643 
1644 			INP_WLOCK_RECHECK(inp);
1645 			if (optval)
1646 				tp->t_flags |= TF_NOPUSH;
1647 			else if (tp->t_flags & TF_NOPUSH) {
1648 				tp->t_flags &= ~TF_NOPUSH;
1649 				if (TCPS_HAVEESTABLISHED(tp->t_state))
1650 					error = tp->t_fb->tfb_tcp_output(tp);
1651 			}
1652 			goto unlock_and_done;
1653 
1654 		case TCP_MAXSEG:
1655 			INP_WUNLOCK(inp);
1656 			error = sooptcopyin(sopt, &optval, sizeof optval,
1657 			    sizeof optval);
1658 			if (error)
1659 				return (error);
1660 
1661 			INP_WLOCK_RECHECK(inp);
1662 			if (optval > 0 && optval <= tp->t_maxseg &&
1663 			    optval + 40 >= V_tcp_minmss)
1664 				tp->t_maxseg = optval;
1665 			else
1666 				error = EINVAL;
1667 			goto unlock_and_done;
1668 
1669 		case TCP_INFO:
1670 			INP_WUNLOCK(inp);
1671 			error = EINVAL;
1672 			break;
1673 
1674 		case TCP_CONGESTION:
1675 			INP_WUNLOCK(inp);
1676 			error = sooptcopyin(sopt, buf, TCP_CA_NAME_MAX - 1, 1);
1677 			if (error)
1678 				break;
1679 			buf[sopt->sopt_valsize] = '\0';
1680 			INP_WLOCK_RECHECK(inp);
1681 			CC_LIST_RLOCK();
1682 			STAILQ_FOREACH(algo, &cc_list, entries)
1683 				if (strncmp(buf, algo->name,
1684 				    TCP_CA_NAME_MAX) == 0)
1685 					break;
1686 			CC_LIST_RUNLOCK();
1687 			if (algo == NULL) {
1688 				INP_WUNLOCK(inp);
1689 				error = EINVAL;
1690 				break;
1691 			}
1692 			/*
1693 			 * We hold a write lock over the tcb so it's safe to
1694 			 * do these things without ordering concerns.
1695 			 */
1696 			if (CC_ALGO(tp)->cb_destroy != NULL)
1697 				CC_ALGO(tp)->cb_destroy(tp->ccv);
1698 			CC_ALGO(tp) = algo;
1699 			/*
1700 			 * If something goes pear shaped initialising the new
1701 			 * algo, fall back to newreno (which does not
1702 			 * require initialisation).
1703 			 */
1704 			if (algo->cb_init != NULL &&
1705 			    algo->cb_init(tp->ccv) != 0) {
1706 				CC_ALGO(tp) = &newreno_cc_algo;
1707 				/*
1708 				 * The only reason init should fail is
1709 				 * because of malloc.
1710 				 */
1711 				error = ENOMEM;
1712 			}
1713 			INP_WUNLOCK(inp);
1714 			break;
1715 
1716 		case TCP_KEEPIDLE:
1717 		case TCP_KEEPINTVL:
1718 		case TCP_KEEPINIT:
1719 			INP_WUNLOCK(inp);
1720 			error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui));
1721 			if (error)
1722 				return (error);
1723 
1724 			if (ui > (UINT_MAX / hz)) {
1725 				error = EINVAL;
1726 				break;
1727 			}
1728 			ui *= hz;
1729 
1730 			INP_WLOCK_RECHECK(inp);
1731 			switch (sopt->sopt_name) {
1732 			case TCP_KEEPIDLE:
1733 				tp->t_keepidle = ui;
1734 				/*
1735 				 * XXX: better check current remaining
1736 				 * timeout and "merge" it with new value.
1737 				 */
1738 				if ((tp->t_state > TCPS_LISTEN) &&
1739 				    (tp->t_state <= TCPS_CLOSING))
1740 					tcp_timer_activate(tp, TT_KEEP,
1741 					    TP_KEEPIDLE(tp));
1742 				break;
1743 			case TCP_KEEPINTVL:
1744 				tp->t_keepintvl = ui;
1745 				if ((tp->t_state == TCPS_FIN_WAIT_2) &&
1746 				    (TP_MAXIDLE(tp) > 0))
1747 					tcp_timer_activate(tp, TT_2MSL,
1748 					    TP_MAXIDLE(tp));
1749 				break;
1750 			case TCP_KEEPINIT:
1751 				tp->t_keepinit = ui;
1752 				if (tp->t_state == TCPS_SYN_RECEIVED ||
1753 				    tp->t_state == TCPS_SYN_SENT)
1754 					tcp_timer_activate(tp, TT_KEEP,
1755 					    TP_KEEPINIT(tp));
1756 				break;
1757 			}
1758 			goto unlock_and_done;
1759 
1760 		case TCP_KEEPCNT:
1761 			INP_WUNLOCK(inp);
1762 			error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui));
1763 			if (error)
1764 				return (error);
1765 
1766 			INP_WLOCK_RECHECK(inp);
1767 			tp->t_keepcnt = ui;
1768 			if ((tp->t_state == TCPS_FIN_WAIT_2) &&
1769 			    (TP_MAXIDLE(tp) > 0))
1770 				tcp_timer_activate(tp, TT_2MSL,
1771 				    TP_MAXIDLE(tp));
1772 			goto unlock_and_done;
1773 
1774 #ifdef TCPPCAP
1775 		case TCP_PCAP_OUT:
1776 		case TCP_PCAP_IN:
1777 			INP_WUNLOCK(inp);
1778 			error = sooptcopyin(sopt, &optval, sizeof optval,
1779 			    sizeof optval);
1780 			if (error)
1781 				return (error);
1782 
1783 			INP_WLOCK_RECHECK(inp);
1784 			if (optval >= 0)
1785 				tcp_pcap_set_sock_max(TCP_PCAP_OUT ?
1786 					&(tp->t_outpkts) : &(tp->t_inpkts),
1787 					optval);
1788 			else
1789 				error = EINVAL;
1790 			goto unlock_and_done;
1791 #endif
1792 
1793 		case TCP_FASTOPEN: {
1794 			struct tcp_fastopen tfo_optval;
1795 
1796 			INP_WUNLOCK(inp);
1797 			if (!V_tcp_fastopen_client_enable &&
1798 			    !V_tcp_fastopen_server_enable)
1799 				return (EPERM);
1800 
1801 			error = sooptcopyin(sopt, &tfo_optval,
1802 				    sizeof(tfo_optval), sizeof(int));
1803 			if (error)
1804 				return (error);
1805 
1806 			INP_WLOCK_RECHECK(inp);
1807 			if (tfo_optval.enable) {
1808 				if (tp->t_state == TCPS_LISTEN) {
1809 					if (!V_tcp_fastopen_server_enable) {
1810 						error = EPERM;
1811 						goto unlock_and_done;
1812 					}
1813 
1814 					tp->t_flags |= TF_FASTOPEN;
1815 					if (tp->t_tfo_pending == NULL)
1816 						tp->t_tfo_pending =
1817 						    tcp_fastopen_alloc_counter();
1818 				} else {
1819 					/*
1820 					 * If a pre-shared key was provided,
1821 					 * stash it in the client cookie
1822 					 * field of the tcpcb for use during
1823 					 * connect.
1824 					 */
1825 					if (sopt->sopt_valsize ==
1826 					    sizeof(tfo_optval)) {
1827 						memcpy(tp->t_tfo_cookie.client,
1828 						       tfo_optval.psk,
1829 						       TCP_FASTOPEN_PSK_LEN);
1830 						tp->t_tfo_client_cookie_len =
1831 						    TCP_FASTOPEN_PSK_LEN;
1832 					}
1833 					tp->t_flags |= TF_FASTOPEN;
1834 				}
1835 			} else
1836 				tp->t_flags &= ~TF_FASTOPEN;
1837 			goto unlock_and_done;
1838 		}
1839 
1840 #ifdef TCP_BLACKBOX
1841 		case TCP_LOG:
1842 			INP_WUNLOCK(inp);
1843 			error = sooptcopyin(sopt, &optval, sizeof optval,
1844 			    sizeof optval);
1845 			if (error)
1846 				return (error);
1847 
1848 			INP_WLOCK_RECHECK(inp);
1849 			error = tcp_log_state_change(tp, optval);
1850 			goto unlock_and_done;
1851 
1852 		case TCP_LOGBUF:
1853 			INP_WUNLOCK(inp);
1854 			error = EINVAL;
1855 			break;
1856 
1857 		case TCP_LOGID:
1858 			INP_WUNLOCK(inp);
1859 			error = sooptcopyin(sopt, buf, TCP_LOG_ID_LEN - 1, 0);
1860 			if (error)
1861 				break;
1862 			buf[sopt->sopt_valsize] = '\0';
1863 			INP_WLOCK_RECHECK(inp);
1864 			error = tcp_log_set_id(tp, buf);
1865 			/* tcp_log_set_id() unlocks the INP. */
1866 			break;
1867 
1868 		case TCP_LOGDUMP:
1869 		case TCP_LOGDUMPID:
1870 			INP_WUNLOCK(inp);
1871 			error =
1872 			    sooptcopyin(sopt, buf, TCP_LOG_REASON_LEN - 1, 0);
1873 			if (error)
1874 				break;
1875 			buf[sopt->sopt_valsize] = '\0';
1876 			INP_WLOCK_RECHECK(inp);
1877 			if (sopt->sopt_name == TCP_LOGDUMP) {
1878 				error = tcp_log_dump_tp_logbuf(tp, buf,
1879 				    M_WAITOK, true);
1880 				INP_WUNLOCK(inp);
1881 			} else {
1882 				tcp_log_dump_tp_bucket_logbufs(tp, buf);
1883 				/*
1884 				 * tcp_log_dump_tp_bucket_logbufs() drops the
1885 				 * INP lock.
1886 				 */
1887 			}
1888 			break;
1889 #endif
1890 
1891 		default:
1892 			INP_WUNLOCK(inp);
1893 			error = ENOPROTOOPT;
1894 			break;
1895 		}
1896 		break;
1897 
1898 	case SOPT_GET:
1899 		tp = intotcpcb(inp);
1900 		switch (sopt->sopt_name) {
1901 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
1902 		case TCP_MD5SIG:
1903 			if (!TCPMD5_ENABLED()) {
1904 				INP_WUNLOCK(inp);
1905 				return (ENOPROTOOPT);
1906 			}
1907 			error = TCPMD5_PCBCTL(inp, sopt);
1908 			break;
1909 #endif
1910 
1911 		case TCP_NODELAY:
1912 			optval = tp->t_flags & TF_NODELAY;
1913 			INP_WUNLOCK(inp);
1914 			error = sooptcopyout(sopt, &optval, sizeof optval);
1915 			break;
1916 		case TCP_MAXSEG:
1917 			optval = tp->t_maxseg;
1918 			INP_WUNLOCK(inp);
1919 			error = sooptcopyout(sopt, &optval, sizeof optval);
1920 			break;
1921 		case TCP_NOOPT:
1922 			optval = tp->t_flags & TF_NOOPT;
1923 			INP_WUNLOCK(inp);
1924 			error = sooptcopyout(sopt, &optval, sizeof optval);
1925 			break;
1926 		case TCP_NOPUSH:
1927 			optval = tp->t_flags & TF_NOPUSH;
1928 			INP_WUNLOCK(inp);
1929 			error = sooptcopyout(sopt, &optval, sizeof optval);
1930 			break;
1931 		case TCP_INFO:
1932 			tcp_fill_info(tp, &ti);
1933 			INP_WUNLOCK(inp);
1934 			error = sooptcopyout(sopt, &ti, sizeof ti);
1935 			break;
1936 		case TCP_CONGESTION:
1937 			len = strlcpy(buf, CC_ALGO(tp)->name, TCP_CA_NAME_MAX);
1938 			INP_WUNLOCK(inp);
1939 			error = sooptcopyout(sopt, buf, len + 1);
1940 			break;
1941 		case TCP_KEEPIDLE:
1942 		case TCP_KEEPINTVL:
1943 		case TCP_KEEPINIT:
1944 		case TCP_KEEPCNT:
1945 			switch (sopt->sopt_name) {
1946 			case TCP_KEEPIDLE:
1947 				ui = TP_KEEPIDLE(tp) / hz;
1948 				break;
1949 			case TCP_KEEPINTVL:
1950 				ui = TP_KEEPINTVL(tp) / hz;
1951 				break;
1952 			case TCP_KEEPINIT:
1953 				ui = TP_KEEPINIT(tp) / hz;
1954 				break;
1955 			case TCP_KEEPCNT:
1956 				ui = TP_KEEPCNT(tp);
1957 				break;
1958 			}
1959 			INP_WUNLOCK(inp);
1960 			error = sooptcopyout(sopt, &ui, sizeof(ui));
1961 			break;
1962 #ifdef TCPPCAP
1963 		case TCP_PCAP_OUT:
1964 		case TCP_PCAP_IN:
1965 			optval = tcp_pcap_get_sock_max(TCP_PCAP_OUT ?
1966 					&(tp->t_outpkts) : &(tp->t_inpkts));
1967 			INP_WUNLOCK(inp);
1968 			error = sooptcopyout(sopt, &optval, sizeof optval);
1969 			break;
1970 #endif
1971 		case TCP_FASTOPEN:
1972 			optval = tp->t_flags & TF_FASTOPEN;
1973 			INP_WUNLOCK(inp);
1974 			error = sooptcopyout(sopt, &optval, sizeof optval);
1975 			break;
1976 #ifdef TCP_BLACKBOX
1977 		case TCP_LOG:
1978 			optval = tp->t_logstate;
1979 			INP_WUNLOCK(inp);
1980 			error = sooptcopyout(sopt, &optval, sizeof(optval));
1981 			break;
1982 		case TCP_LOGBUF:
1983 			/* tcp_log_getlogbuf() does INP_WUNLOCK(inp) */
1984 			error = tcp_log_getlogbuf(sopt, tp);
1985 			break;
1986 		case TCP_LOGID:
1987 			len = tcp_log_get_id(tp, buf);
1988 			INP_WUNLOCK(inp);
1989 			error = sooptcopyout(sopt, buf, len + 1);
1990 			break;
1991 		case TCP_LOGDUMP:
1992 		case TCP_LOGDUMPID:
1993 			INP_WUNLOCK(inp);
1994 			error = EINVAL;
1995 			break;
1996 #endif
1997 		default:
1998 			INP_WUNLOCK(inp);
1999 			error = ENOPROTOOPT;
2000 			break;
2001 		}
2002 		break;
2003 	}
2004 	return (error);
2005 }
2006 #undef INP_WLOCK_RECHECK
2007 #undef INP_WLOCK_RECHECK_CLEANUP
2008 
2009 /*
2010  * Attach TCP protocol to socket, allocating
2011  * internet protocol control block, tcp control block,
2012  * bufer space, and entering LISTEN state if to accept connections.
2013  */
2014 static int
2015 tcp_attach(struct socket *so)
2016 {
2017 	struct tcpcb *tp;
2018 	struct inpcb *inp;
2019 	int error;
2020 
2021 	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
2022 		error = soreserve(so, V_tcp_sendspace, V_tcp_recvspace);
2023 		if (error)
2024 			return (error);
2025 	}
2026 	so->so_rcv.sb_flags |= SB_AUTOSIZE;
2027 	so->so_snd.sb_flags |= SB_AUTOSIZE;
2028 	INP_INFO_RLOCK(&V_tcbinfo);
2029 	error = in_pcballoc(so, &V_tcbinfo);
2030 	if (error) {
2031 		INP_INFO_RUNLOCK(&V_tcbinfo);
2032 		return (error);
2033 	}
2034 	inp = sotoinpcb(so);
2035 #ifdef INET6
2036 	if (inp->inp_vflag & INP_IPV6PROTO) {
2037 		inp->inp_vflag |= INP_IPV6;
2038 		if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
2039 			inp->inp_vflag |= INP_IPV4;
2040 		inp->in6p_hops = -1;	/* use kernel default */
2041 	}
2042 	else
2043 #endif
2044 	inp->inp_vflag |= INP_IPV4;
2045 	tp = tcp_newtcpcb(inp);
2046 	if (tp == NULL) {
2047 		in_pcbdetach(inp);
2048 		in_pcbfree(inp);
2049 		INP_INFO_RUNLOCK(&V_tcbinfo);
2050 		return (ENOBUFS);
2051 	}
2052 	tp->t_state = TCPS_CLOSED;
2053 	INP_WUNLOCK(inp);
2054 	INP_INFO_RUNLOCK(&V_tcbinfo);
2055 	TCPSTATES_INC(TCPS_CLOSED);
2056 	return (0);
2057 }
2058 
2059 /*
2060  * Initiate (or continue) disconnect.
2061  * If embryonic state, just send reset (once).
2062  * If in ``let data drain'' option and linger null, just drop.
2063  * Otherwise (hard), mark socket disconnecting and drop
2064  * current input data; switch states based on user close, and
2065  * send segment to peer (with FIN).
2066  */
2067 static void
2068 tcp_disconnect(struct tcpcb *tp)
2069 {
2070 	struct inpcb *inp = tp->t_inpcb;
2071 	struct socket *so = inp->inp_socket;
2072 
2073 	INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
2074 	INP_WLOCK_ASSERT(inp);
2075 
2076 	/*
2077 	 * Neither tcp_close() nor tcp_drop() should return NULL, as the
2078 	 * socket is still open.
2079 	 */
2080 	if (tp->t_state < TCPS_ESTABLISHED) {
2081 		tp = tcp_close(tp);
2082 		KASSERT(tp != NULL,
2083 		    ("tcp_disconnect: tcp_close() returned NULL"));
2084 	} else if ((so->so_options & SO_LINGER) && so->so_linger == 0) {
2085 		tp = tcp_drop(tp, 0);
2086 		KASSERT(tp != NULL,
2087 		    ("tcp_disconnect: tcp_drop() returned NULL"));
2088 	} else {
2089 		soisdisconnecting(so);
2090 		sbflush(&so->so_rcv);
2091 		tcp_usrclosed(tp);
2092 		if (!(inp->inp_flags & INP_DROPPED))
2093 			tp->t_fb->tfb_tcp_output(tp);
2094 	}
2095 }
2096 
2097 /*
2098  * User issued close, and wish to trail through shutdown states:
2099  * if never received SYN, just forget it.  If got a SYN from peer,
2100  * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
2101  * If already got a FIN from peer, then almost done; go to LAST_ACK
2102  * state.  In all other cases, have already sent FIN to peer (e.g.
2103  * after PRU_SHUTDOWN), and just have to play tedious game waiting
2104  * for peer to send FIN or not respond to keep-alives, etc.
2105  * We can let the user exit from the close as soon as the FIN is acked.
2106  */
2107 static void
2108 tcp_usrclosed(struct tcpcb *tp)
2109 {
2110 
2111 	INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
2112 	INP_WLOCK_ASSERT(tp->t_inpcb);
2113 
2114 	switch (tp->t_state) {
2115 	case TCPS_LISTEN:
2116 #ifdef TCP_OFFLOAD
2117 		tcp_offload_listen_stop(tp);
2118 #endif
2119 		tcp_state_change(tp, TCPS_CLOSED);
2120 		/* FALLTHROUGH */
2121 	case TCPS_CLOSED:
2122 		tp = tcp_close(tp);
2123 		/*
2124 		 * tcp_close() should never return NULL here as the socket is
2125 		 * still open.
2126 		 */
2127 		KASSERT(tp != NULL,
2128 		    ("tcp_usrclosed: tcp_close() returned NULL"));
2129 		break;
2130 
2131 	case TCPS_SYN_SENT:
2132 	case TCPS_SYN_RECEIVED:
2133 		tp->t_flags |= TF_NEEDFIN;
2134 		break;
2135 
2136 	case TCPS_ESTABLISHED:
2137 		tcp_state_change(tp, TCPS_FIN_WAIT_1);
2138 		break;
2139 
2140 	case TCPS_CLOSE_WAIT:
2141 		tcp_state_change(tp, TCPS_LAST_ACK);
2142 		break;
2143 	}
2144 	if (tp->t_state >= TCPS_FIN_WAIT_2) {
2145 		soisdisconnected(tp->t_inpcb->inp_socket);
2146 		/* Prevent the connection hanging in FIN_WAIT_2 forever. */
2147 		if (tp->t_state == TCPS_FIN_WAIT_2) {
2148 			int timeout;
2149 
2150 			timeout = (tcp_fast_finwait2_recycle) ?
2151 			    tcp_finwait2_timeout : TP_MAXIDLE(tp);
2152 			tcp_timer_activate(tp, TT_2MSL, timeout);
2153 		}
2154 	}
2155 }
2156 
2157 #ifdef DDB
2158 static void
2159 db_print_indent(int indent)
2160 {
2161 	int i;
2162 
2163 	for (i = 0; i < indent; i++)
2164 		db_printf(" ");
2165 }
2166 
2167 static void
2168 db_print_tstate(int t_state)
2169 {
2170 
2171 	switch (t_state) {
2172 	case TCPS_CLOSED:
2173 		db_printf("TCPS_CLOSED");
2174 		return;
2175 
2176 	case TCPS_LISTEN:
2177 		db_printf("TCPS_LISTEN");
2178 		return;
2179 
2180 	case TCPS_SYN_SENT:
2181 		db_printf("TCPS_SYN_SENT");
2182 		return;
2183 
2184 	case TCPS_SYN_RECEIVED:
2185 		db_printf("TCPS_SYN_RECEIVED");
2186 		return;
2187 
2188 	case TCPS_ESTABLISHED:
2189 		db_printf("TCPS_ESTABLISHED");
2190 		return;
2191 
2192 	case TCPS_CLOSE_WAIT:
2193 		db_printf("TCPS_CLOSE_WAIT");
2194 		return;
2195 
2196 	case TCPS_FIN_WAIT_1:
2197 		db_printf("TCPS_FIN_WAIT_1");
2198 		return;
2199 
2200 	case TCPS_CLOSING:
2201 		db_printf("TCPS_CLOSING");
2202 		return;
2203 
2204 	case TCPS_LAST_ACK:
2205 		db_printf("TCPS_LAST_ACK");
2206 		return;
2207 
2208 	case TCPS_FIN_WAIT_2:
2209 		db_printf("TCPS_FIN_WAIT_2");
2210 		return;
2211 
2212 	case TCPS_TIME_WAIT:
2213 		db_printf("TCPS_TIME_WAIT");
2214 		return;
2215 
2216 	default:
2217 		db_printf("unknown");
2218 		return;
2219 	}
2220 }
2221 
2222 static void
2223 db_print_tflags(u_int t_flags)
2224 {
2225 	int comma;
2226 
2227 	comma = 0;
2228 	if (t_flags & TF_ACKNOW) {
2229 		db_printf("%sTF_ACKNOW", comma ? ", " : "");
2230 		comma = 1;
2231 	}
2232 	if (t_flags & TF_DELACK) {
2233 		db_printf("%sTF_DELACK", comma ? ", " : "");
2234 		comma = 1;
2235 	}
2236 	if (t_flags & TF_NODELAY) {
2237 		db_printf("%sTF_NODELAY", comma ? ", " : "");
2238 		comma = 1;
2239 	}
2240 	if (t_flags & TF_NOOPT) {
2241 		db_printf("%sTF_NOOPT", comma ? ", " : "");
2242 		comma = 1;
2243 	}
2244 	if (t_flags & TF_SENTFIN) {
2245 		db_printf("%sTF_SENTFIN", comma ? ", " : "");
2246 		comma = 1;
2247 	}
2248 	if (t_flags & TF_REQ_SCALE) {
2249 		db_printf("%sTF_REQ_SCALE", comma ? ", " : "");
2250 		comma = 1;
2251 	}
2252 	if (t_flags & TF_RCVD_SCALE) {
2253 		db_printf("%sTF_RECVD_SCALE", comma ? ", " : "");
2254 		comma = 1;
2255 	}
2256 	if (t_flags & TF_REQ_TSTMP) {
2257 		db_printf("%sTF_REQ_TSTMP", comma ? ", " : "");
2258 		comma = 1;
2259 	}
2260 	if (t_flags & TF_RCVD_TSTMP) {
2261 		db_printf("%sTF_RCVD_TSTMP", comma ? ", " : "");
2262 		comma = 1;
2263 	}
2264 	if (t_flags & TF_SACK_PERMIT) {
2265 		db_printf("%sTF_SACK_PERMIT", comma ? ", " : "");
2266 		comma = 1;
2267 	}
2268 	if (t_flags & TF_NEEDSYN) {
2269 		db_printf("%sTF_NEEDSYN", comma ? ", " : "");
2270 		comma = 1;
2271 	}
2272 	if (t_flags & TF_NEEDFIN) {
2273 		db_printf("%sTF_NEEDFIN", comma ? ", " : "");
2274 		comma = 1;
2275 	}
2276 	if (t_flags & TF_NOPUSH) {
2277 		db_printf("%sTF_NOPUSH", comma ? ", " : "");
2278 		comma = 1;
2279 	}
2280 	if (t_flags & TF_MORETOCOME) {
2281 		db_printf("%sTF_MORETOCOME", comma ? ", " : "");
2282 		comma = 1;
2283 	}
2284 	if (t_flags & TF_LQ_OVERFLOW) {
2285 		db_printf("%sTF_LQ_OVERFLOW", comma ? ", " : "");
2286 		comma = 1;
2287 	}
2288 	if (t_flags & TF_LASTIDLE) {
2289 		db_printf("%sTF_LASTIDLE", comma ? ", " : "");
2290 		comma = 1;
2291 	}
2292 	if (t_flags & TF_RXWIN0SENT) {
2293 		db_printf("%sTF_RXWIN0SENT", comma ? ", " : "");
2294 		comma = 1;
2295 	}
2296 	if (t_flags & TF_FASTRECOVERY) {
2297 		db_printf("%sTF_FASTRECOVERY", comma ? ", " : "");
2298 		comma = 1;
2299 	}
2300 	if (t_flags & TF_CONGRECOVERY) {
2301 		db_printf("%sTF_CONGRECOVERY", comma ? ", " : "");
2302 		comma = 1;
2303 	}
2304 	if (t_flags & TF_WASFRECOVERY) {
2305 		db_printf("%sTF_WASFRECOVERY", comma ? ", " : "");
2306 		comma = 1;
2307 	}
2308 	if (t_flags & TF_SIGNATURE) {
2309 		db_printf("%sTF_SIGNATURE", comma ? ", " : "");
2310 		comma = 1;
2311 	}
2312 	if (t_flags & TF_FORCEDATA) {
2313 		db_printf("%sTF_FORCEDATA", comma ? ", " : "");
2314 		comma = 1;
2315 	}
2316 	if (t_flags & TF_TSO) {
2317 		db_printf("%sTF_TSO", comma ? ", " : "");
2318 		comma = 1;
2319 	}
2320 	if (t_flags & TF_ECN_PERMIT) {
2321 		db_printf("%sTF_ECN_PERMIT", comma ? ", " : "");
2322 		comma = 1;
2323 	}
2324 	if (t_flags & TF_FASTOPEN) {
2325 		db_printf("%sTF_FASTOPEN", comma ? ", " : "");
2326 		comma = 1;
2327 	}
2328 }
2329 
2330 static void
2331 db_print_toobflags(char t_oobflags)
2332 {
2333 	int comma;
2334 
2335 	comma = 0;
2336 	if (t_oobflags & TCPOOB_HAVEDATA) {
2337 		db_printf("%sTCPOOB_HAVEDATA", comma ? ", " : "");
2338 		comma = 1;
2339 	}
2340 	if (t_oobflags & TCPOOB_HADDATA) {
2341 		db_printf("%sTCPOOB_HADDATA", comma ? ", " : "");
2342 		comma = 1;
2343 	}
2344 }
2345 
2346 static void
2347 db_print_tcpcb(struct tcpcb *tp, const char *name, int indent)
2348 {
2349 
2350 	db_print_indent(indent);
2351 	db_printf("%s at %p\n", name, tp);
2352 
2353 	indent += 2;
2354 
2355 	db_print_indent(indent);
2356 	db_printf("t_segq first: %p   t_segqlen: %d   t_dupacks: %d\n",
2357 	   LIST_FIRST(&tp->t_segq), tp->t_segqlen, tp->t_dupacks);
2358 
2359 	db_print_indent(indent);
2360 	db_printf("tt_rexmt: %p   tt_persist: %p   tt_keep: %p\n",
2361 	    &tp->t_timers->tt_rexmt, &tp->t_timers->tt_persist, &tp->t_timers->tt_keep);
2362 
2363 	db_print_indent(indent);
2364 	db_printf("tt_2msl: %p   tt_delack: %p   t_inpcb: %p\n", &tp->t_timers->tt_2msl,
2365 	    &tp->t_timers->tt_delack, tp->t_inpcb);
2366 
2367 	db_print_indent(indent);
2368 	db_printf("t_state: %d (", tp->t_state);
2369 	db_print_tstate(tp->t_state);
2370 	db_printf(")\n");
2371 
2372 	db_print_indent(indent);
2373 	db_printf("t_flags: 0x%x (", tp->t_flags);
2374 	db_print_tflags(tp->t_flags);
2375 	db_printf(")\n");
2376 
2377 	db_print_indent(indent);
2378 	db_printf("snd_una: 0x%08x   snd_max: 0x%08x   snd_nxt: x0%08x\n",
2379 	    tp->snd_una, tp->snd_max, tp->snd_nxt);
2380 
2381 	db_print_indent(indent);
2382 	db_printf("snd_up: 0x%08x   snd_wl1: 0x%08x   snd_wl2: 0x%08x\n",
2383 	   tp->snd_up, tp->snd_wl1, tp->snd_wl2);
2384 
2385 	db_print_indent(indent);
2386 	db_printf("iss: 0x%08x   irs: 0x%08x   rcv_nxt: 0x%08x\n",
2387 	    tp->iss, tp->irs, tp->rcv_nxt);
2388 
2389 	db_print_indent(indent);
2390 	db_printf("rcv_adv: 0x%08x   rcv_wnd: %u   rcv_up: 0x%08x\n",
2391 	    tp->rcv_adv, tp->rcv_wnd, tp->rcv_up);
2392 
2393 	db_print_indent(indent);
2394 	db_printf("snd_wnd: %u   snd_cwnd: %u\n",
2395 	   tp->snd_wnd, tp->snd_cwnd);
2396 
2397 	db_print_indent(indent);
2398 	db_printf("snd_ssthresh: %u   snd_recover: "
2399 	    "0x%08x\n", tp->snd_ssthresh, tp->snd_recover);
2400 
2401 	db_print_indent(indent);
2402 	db_printf("t_rcvtime: %u   t_startime: %u\n",
2403 	    tp->t_rcvtime, tp->t_starttime);
2404 
2405 	db_print_indent(indent);
2406 	db_printf("t_rttime: %u   t_rtsq: 0x%08x\n",
2407 	    tp->t_rtttime, tp->t_rtseq);
2408 
2409 	db_print_indent(indent);
2410 	db_printf("t_rxtcur: %d   t_maxseg: %u   t_srtt: %d\n",
2411 	    tp->t_rxtcur, tp->t_maxseg, tp->t_srtt);
2412 
2413 	db_print_indent(indent);
2414 	db_printf("t_rttvar: %d   t_rxtshift: %d   t_rttmin: %u   "
2415 	    "t_rttbest: %u\n", tp->t_rttvar, tp->t_rxtshift, tp->t_rttmin,
2416 	    tp->t_rttbest);
2417 
2418 	db_print_indent(indent);
2419 	db_printf("t_rttupdated: %lu   max_sndwnd: %u   t_softerror: %d\n",
2420 	    tp->t_rttupdated, tp->max_sndwnd, tp->t_softerror);
2421 
2422 	db_print_indent(indent);
2423 	db_printf("t_oobflags: 0x%x (", tp->t_oobflags);
2424 	db_print_toobflags(tp->t_oobflags);
2425 	db_printf(")   t_iobc: 0x%02x\n", tp->t_iobc);
2426 
2427 	db_print_indent(indent);
2428 	db_printf("snd_scale: %u   rcv_scale: %u   request_r_scale: %u\n",
2429 	    tp->snd_scale, tp->rcv_scale, tp->request_r_scale);
2430 
2431 	db_print_indent(indent);
2432 	db_printf("ts_recent: %u   ts_recent_age: %u\n",
2433 	    tp->ts_recent, tp->ts_recent_age);
2434 
2435 	db_print_indent(indent);
2436 	db_printf("ts_offset: %u   last_ack_sent: 0x%08x   snd_cwnd_prev: "
2437 	    "%u\n", tp->ts_offset, tp->last_ack_sent, tp->snd_cwnd_prev);
2438 
2439 	db_print_indent(indent);
2440 	db_printf("snd_ssthresh_prev: %u   snd_recover_prev: 0x%08x   "
2441 	    "t_badrxtwin: %u\n", tp->snd_ssthresh_prev,
2442 	    tp->snd_recover_prev, tp->t_badrxtwin);
2443 
2444 	db_print_indent(indent);
2445 	db_printf("snd_numholes: %d  snd_holes first: %p\n",
2446 	    tp->snd_numholes, TAILQ_FIRST(&tp->snd_holes));
2447 
2448 	db_print_indent(indent);
2449 	db_printf("snd_fack: 0x%08x   rcv_numsacks: %d   sack_newdata: "
2450 	    "0x%08x\n", tp->snd_fack, tp->rcv_numsacks, tp->sack_newdata);
2451 
2452 	/* Skip sackblks, sackhint. */
2453 
2454 	db_print_indent(indent);
2455 	db_printf("t_rttlow: %d   rfbuf_ts: %u   rfbuf_cnt: %d\n",
2456 	    tp->t_rttlow, tp->rfbuf_ts, tp->rfbuf_cnt);
2457 }
2458 
2459 DB_SHOW_COMMAND(tcpcb, db_show_tcpcb)
2460 {
2461 	struct tcpcb *tp;
2462 
2463 	if (!have_addr) {
2464 		db_printf("usage: show tcpcb <addr>\n");
2465 		return;
2466 	}
2467 	tp = (struct tcpcb *)addr;
2468 
2469 	db_print_tcpcb(tp, "tcpcb", 0);
2470 }
2471 #endif
2472