xref: /freebsd/sys/netinet/tcp_usrreq.c (revision 3f2508b7f3855102abed99b846e30e728ba3d04d)
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_kern_tls.h"
48 #include "opt_tcpdebug.h"
49 
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/arb.h>
53 #include <sys/limits.h>
54 #include <sys/malloc.h>
55 #include <sys/refcount.h>
56 #include <sys/kernel.h>
57 #include <sys/ktls.h>
58 #include <sys/qmath.h>
59 #include <sys/sysctl.h>
60 #include <sys/mbuf.h>
61 #ifdef INET6
62 #include <sys/domain.h>
63 #endif /* INET6 */
64 #include <sys/socket.h>
65 #include <sys/socketvar.h>
66 #include <sys/protosw.h>
67 #include <sys/proc.h>
68 #include <sys/jail.h>
69 #include <sys/syslog.h>
70 #include <sys/stats.h>
71 
72 #ifdef DDB
73 #include <ddb/ddb.h>
74 #endif
75 
76 #include <net/if.h>
77 #include <net/if_var.h>
78 #include <net/route.h>
79 #include <net/vnet.h>
80 
81 #include <netinet/in.h>
82 #include <netinet/in_kdtrace.h>
83 #include <netinet/in_pcb.h>
84 #include <netinet/in_systm.h>
85 #include <netinet/in_var.h>
86 #include <netinet/ip_var.h>
87 #ifdef INET6
88 #include <netinet/ip6.h>
89 #include <netinet6/in6_pcb.h>
90 #include <netinet6/ip6_var.h>
91 #include <netinet6/scope6_var.h>
92 #endif
93 #include <netinet/tcp.h>
94 #include <netinet/tcp_fsm.h>
95 #include <netinet/tcp_seq.h>
96 #include <netinet/tcp_timer.h>
97 #include <netinet/tcp_var.h>
98 #include <netinet/tcp_log_buf.h>
99 #include <netinet/tcpip.h>
100 #include <netinet/cc/cc.h>
101 #include <netinet/tcp_fastopen.h>
102 #include <netinet/tcp_hpts.h>
103 #ifdef TCPPCAP
104 #include <netinet/tcp_pcap.h>
105 #endif
106 #ifdef TCPDEBUG
107 #include <netinet/tcp_debug.h>
108 #endif
109 #ifdef TCP_OFFLOAD
110 #include <netinet/tcp_offload.h>
111 #endif
112 #include <netipsec/ipsec_support.h>
113 
114 #include <vm/vm.h>
115 #include <vm/vm_param.h>
116 #include <vm/pmap.h>
117 #include <vm/vm_extern.h>
118 #include <vm/vm_map.h>
119 #include <vm/vm_page.h>
120 
121 /*
122  * TCP protocol interface to socket abstraction.
123  */
124 #ifdef INET
125 static int	tcp_connect(struct tcpcb *, struct sockaddr *,
126 		    struct thread *td);
127 #endif /* INET */
128 #ifdef INET6
129 static int	tcp6_connect(struct tcpcb *, struct sockaddr *,
130 		    struct thread *td);
131 #endif /* INET6 */
132 static void	tcp_disconnect(struct tcpcb *);
133 static void	tcp_usrclosed(struct tcpcb *);
134 static void	tcp_fill_info(struct tcpcb *, struct tcp_info *);
135 
136 static int	tcp_pru_options_support(struct tcpcb *tp, int flags);
137 
138 #ifdef TCPDEBUG
139 #define	TCPDEBUG0	int ostate = 0
140 #define	TCPDEBUG1()	ostate = tp ? tp->t_state : 0
141 #define	TCPDEBUG2(req)	if (tp && (so->so_options & SO_DEBUG)) \
142 				tcp_trace(TA_USER, ostate, tp, 0, 0, req)
143 #else
144 #define	TCPDEBUG0
145 #define	TCPDEBUG1()
146 #define	TCPDEBUG2(req)
147 #endif
148 
149 /*
150  * tcp_require_unique port requires a globally-unique source port for each
151  * outgoing connection.  The default is to require the 4-tuple to be unique.
152  */
153 VNET_DEFINE(int, tcp_require_unique_port) = 0;
154 SYSCTL_INT(_net_inet_tcp, OID_AUTO, require_unique_port,
155     CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_require_unique_port), 0,
156     "Require globally-unique ephemeral port for outgoing connections");
157 #define	V_tcp_require_unique_port	VNET(tcp_require_unique_port)
158 
159 /*
160  * TCP attaches to socket via pru_attach(), reserving space,
161  * and an internet control block.
162  */
163 static int
164 tcp_usr_attach(struct socket *so, int proto, struct thread *td)
165 {
166 	struct inpcb *inp;
167 	struct tcpcb *tp = NULL;
168 	int error;
169 	TCPDEBUG0;
170 
171 	inp = sotoinpcb(so);
172 	KASSERT(inp == NULL, ("tcp_usr_attach: inp != NULL"));
173 	TCPDEBUG1();
174 
175 	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
176 		error = soreserve(so, V_tcp_sendspace, V_tcp_recvspace);
177 		if (error)
178 			goto out;
179 	}
180 
181 	so->so_rcv.sb_flags |= SB_AUTOSIZE;
182 	so->so_snd.sb_flags |= SB_AUTOSIZE;
183 	error = in_pcballoc(so, &V_tcbinfo);
184 	if (error)
185 		goto out;
186 	inp = sotoinpcb(so);
187 #ifdef INET6
188 	if (inp->inp_vflag & INP_IPV6PROTO) {
189 		inp->inp_vflag |= INP_IPV6;
190 		if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
191 			inp->inp_vflag |= INP_IPV4;
192 		inp->in6p_hops = -1;	/* use kernel default */
193 	}
194 	else
195 #endif
196 		inp->inp_vflag |= INP_IPV4;
197 	tp = tcp_newtcpcb(inp);
198 	if (tp == NULL) {
199 		error = ENOBUFS;
200 		in_pcbdetach(inp);
201 		in_pcbfree(inp);
202 		goto out;
203 	}
204 	tp->t_state = TCPS_CLOSED;
205 	INP_WUNLOCK(inp);
206 	TCPSTATES_INC(TCPS_CLOSED);
207 out:
208 	TCPDEBUG2(PRU_ATTACH);
209 	TCP_PROBE2(debug__user, tp, PRU_ATTACH);
210 	return (error);
211 }
212 
213 /*
214  * tcp_usr_detach is called when the socket layer loses its final reference
215  * to the socket, be it a file descriptor reference, a reference from TCP,
216  * etc.  At this point, there is only one case in which we will keep around
217  * inpcb state: time wait.
218  */
219 static void
220 tcp_usr_detach(struct socket *so)
221 {
222 	struct inpcb *inp;
223 	struct tcpcb *tp;
224 
225 	inp = sotoinpcb(so);
226 	KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
227 	INP_WLOCK(inp);
228 	KASSERT(so->so_pcb == inp && inp->inp_socket == so,
229 		("%s: socket %p inp %p mismatch", __func__, so, inp));
230 
231 	tp = intotcpcb(inp);
232 
233 	if (inp->inp_flags & INP_TIMEWAIT) {
234 		/*
235 		 * There are two cases to handle: one in which the time wait
236 		 * state is being discarded (INP_DROPPED), and one in which
237 		 * this connection will remain in timewait.  In the former,
238 		 * it is time to discard all state (except tcptw, which has
239 		 * already been discarded by the timewait close code, which
240 		 * should be further up the call stack somewhere).  In the
241 		 * latter case, we detach from the socket, but leave the pcb
242 		 * present until timewait ends.
243 		 *
244 		 * XXXRW: Would it be cleaner to free the tcptw here?
245 		 *
246 		 * Astute question indeed, from twtcp perspective there are
247 		 * four cases to consider:
248 		 *
249 		 * #1 tcp_usr_detach is called at tcptw creation time by
250 		 *  tcp_twstart, then do not discard the newly created tcptw
251 		 *  and leave inpcb present until timewait ends
252 		 * #2 tcp_usr_detach is called at tcptw creation time by
253 		 *  tcp_twstart, but connection is local and tw will be
254 		 *  discarded immediately
255 		 * #3 tcp_usr_detach is called at timewait end (or reuse) by
256 		 *  tcp_twclose, then the tcptw has already been discarded
257 		 *  (or reused) and inpcb is freed here
258 		 * #4 tcp_usr_detach is called() after timewait ends (or reuse)
259 		 *  (e.g. by soclose), then tcptw has already been discarded
260 		 *  (or reused) and inpcb is freed here
261 		 *
262 		 *  In all three cases the tcptw should not be freed here.
263 		 */
264 		if (inp->inp_flags & INP_DROPPED) {
265 			in_pcbdetach(inp);
266 			if (__predict_true(tp == NULL)) {
267 				in_pcbfree(inp);
268 			} else {
269 				/*
270 				 * This case should not happen as in TIMEWAIT
271 				 * state the inp should not be destroyed before
272 				 * its tcptw.  If INVARIANTS is defined, panic.
273 				 */
274 #ifdef INVARIANTS
275 				panic("%s: Panic before an inp double-free: "
276 				    "INP_TIMEWAIT && INP_DROPPED && tp != NULL"
277 				    , __func__);
278 #else
279 				log(LOG_ERR, "%s: Avoid an inp double-free: "
280 				    "INP_TIMEWAIT && INP_DROPPED && tp != NULL"
281 				    , __func__);
282 #endif
283 				INP_WUNLOCK(inp);
284 			}
285 		} else {
286 			in_pcbdetach(inp);
287 			INP_WUNLOCK(inp);
288 		}
289 	} else {
290 		/*
291 		 * If the connection is not in timewait, we consider two
292 		 * two conditions: one in which no further processing is
293 		 * necessary (dropped || embryonic), and one in which TCP is
294 		 * not yet done, but no longer requires the socket, so the
295 		 * pcb will persist for the time being.
296 		 *
297 		 * XXXRW: Does the second case still occur?
298 		 */
299 		if (inp->inp_flags & INP_DROPPED ||
300 		    tp->t_state < TCPS_SYN_SENT) {
301 			tcp_discardcb(tp);
302 			in_pcbdetach(inp);
303 			in_pcbfree(inp);
304 		} else {
305 			in_pcbdetach(inp);
306 			INP_WUNLOCK(inp);
307 		}
308 	}
309 }
310 
311 #ifdef INET
312 /*
313  * Give the socket an address.
314  */
315 static int
316 tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
317 {
318 	int error = 0;
319 	struct inpcb *inp;
320 	struct tcpcb *tp = NULL;
321 	struct sockaddr_in *sinp;
322 
323 	sinp = (struct sockaddr_in *)nam;
324 	if (nam->sa_family != AF_INET)
325 		return (EAFNOSUPPORT);
326 	if (nam->sa_len != sizeof(*sinp))
327 		return (EINVAL);
328 
329 	/*
330 	 * Must check for multicast addresses and disallow binding
331 	 * to them.
332 	 */
333 	if (IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
334 		return (EAFNOSUPPORT);
335 
336 	TCPDEBUG0;
337 	inp = sotoinpcb(so);
338 	KASSERT(inp != NULL, ("tcp_usr_bind: inp == NULL"));
339 	INP_WLOCK(inp);
340 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
341 		error = EINVAL;
342 		goto out;
343 	}
344 	tp = intotcpcb(inp);
345 	TCPDEBUG1();
346 	INP_HASH_WLOCK(&V_tcbinfo);
347 	error = in_pcbbind(inp, nam, td->td_ucred);
348 	INP_HASH_WUNLOCK(&V_tcbinfo);
349 out:
350 	TCPDEBUG2(PRU_BIND);
351 	TCP_PROBE2(debug__user, tp, PRU_BIND);
352 	INP_WUNLOCK(inp);
353 
354 	return (error);
355 }
356 #endif /* INET */
357 
358 #ifdef INET6
359 static int
360 tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
361 {
362 	int error = 0;
363 	struct inpcb *inp;
364 	struct tcpcb *tp = NULL;
365 	struct sockaddr_in6 *sin6;
366 	u_char vflagsav;
367 
368 	sin6 = (struct sockaddr_in6 *)nam;
369 	if (nam->sa_family != AF_INET6)
370 		return (EAFNOSUPPORT);
371 	if (nam->sa_len != sizeof(*sin6))
372 		return (EINVAL);
373 
374 	/*
375 	 * Must check for multicast addresses and disallow binding
376 	 * to them.
377 	 */
378 	if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
379 		return (EAFNOSUPPORT);
380 
381 	TCPDEBUG0;
382 	inp = sotoinpcb(so);
383 	KASSERT(inp != NULL, ("tcp6_usr_bind: inp == NULL"));
384 	INP_WLOCK(inp);
385 	vflagsav = inp->inp_vflag;
386 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
387 		error = EINVAL;
388 		goto out;
389 	}
390 	tp = intotcpcb(inp);
391 	TCPDEBUG1();
392 	INP_HASH_WLOCK(&V_tcbinfo);
393 	inp->inp_vflag &= ~INP_IPV4;
394 	inp->inp_vflag |= INP_IPV6;
395 #ifdef INET
396 	if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
397 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr))
398 			inp->inp_vflag |= INP_IPV4;
399 		else if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
400 			struct sockaddr_in sin;
401 
402 			in6_sin6_2_sin(&sin, sin6);
403 			if (IN_MULTICAST(ntohl(sin.sin_addr.s_addr))) {
404 				error = EAFNOSUPPORT;
405 				INP_HASH_WUNLOCK(&V_tcbinfo);
406 				goto out;
407 			}
408 			inp->inp_vflag |= INP_IPV4;
409 			inp->inp_vflag &= ~INP_IPV6;
410 			error = in_pcbbind(inp, (struct sockaddr *)&sin,
411 			    td->td_ucred);
412 			INP_HASH_WUNLOCK(&V_tcbinfo);
413 			goto out;
414 		}
415 	}
416 #endif
417 	error = in6_pcbbind(inp, nam, td->td_ucred);
418 	INP_HASH_WUNLOCK(&V_tcbinfo);
419 out:
420 	if (error != 0)
421 		inp->inp_vflag = vflagsav;
422 	TCPDEBUG2(PRU_BIND);
423 	TCP_PROBE2(debug__user, tp, PRU_BIND);
424 	INP_WUNLOCK(inp);
425 	return (error);
426 }
427 #endif /* INET6 */
428 
429 #ifdef INET
430 /*
431  * Prepare to accept connections.
432  */
433 static int
434 tcp_usr_listen(struct socket *so, int backlog, struct thread *td)
435 {
436 	int error = 0;
437 	struct inpcb *inp;
438 	struct tcpcb *tp = NULL;
439 
440 	TCPDEBUG0;
441 	inp = sotoinpcb(so);
442 	KASSERT(inp != NULL, ("tcp_usr_listen: inp == NULL"));
443 	INP_WLOCK(inp);
444 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
445 		error = EINVAL;
446 		goto out;
447 	}
448 	tp = intotcpcb(inp);
449 	TCPDEBUG1();
450 	SOCK_LOCK(so);
451 	error = solisten_proto_check(so);
452 	INP_HASH_WLOCK(&V_tcbinfo);
453 	if (error == 0 && inp->inp_lport == 0)
454 		error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
455 	INP_HASH_WUNLOCK(&V_tcbinfo);
456 	if (error == 0) {
457 		tcp_state_change(tp, TCPS_LISTEN);
458 		solisten_proto(so, backlog);
459 #ifdef TCP_OFFLOAD
460 		if ((so->so_options & SO_NO_OFFLOAD) == 0)
461 			tcp_offload_listen_start(tp);
462 #endif
463 	}
464 	SOCK_UNLOCK(so);
465 
466 	if (IS_FASTOPEN(tp->t_flags))
467 		tp->t_tfo_pending = tcp_fastopen_alloc_counter();
468 
469 out:
470 	TCPDEBUG2(PRU_LISTEN);
471 	TCP_PROBE2(debug__user, tp, PRU_LISTEN);
472 	INP_WUNLOCK(inp);
473 	return (error);
474 }
475 #endif /* INET */
476 
477 #ifdef INET6
478 static int
479 tcp6_usr_listen(struct socket *so, int backlog, struct thread *td)
480 {
481 	int error = 0;
482 	struct inpcb *inp;
483 	struct tcpcb *tp = NULL;
484 	u_char vflagsav;
485 
486 	TCPDEBUG0;
487 	inp = sotoinpcb(so);
488 	KASSERT(inp != NULL, ("tcp6_usr_listen: inp == NULL"));
489 	INP_WLOCK(inp);
490 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
491 		error = EINVAL;
492 		goto out;
493 	}
494 	vflagsav = inp->inp_vflag;
495 	tp = intotcpcb(inp);
496 	TCPDEBUG1();
497 	SOCK_LOCK(so);
498 	error = solisten_proto_check(so);
499 	INP_HASH_WLOCK(&V_tcbinfo);
500 	if (error == 0 && inp->inp_lport == 0) {
501 		inp->inp_vflag &= ~INP_IPV4;
502 		if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
503 			inp->inp_vflag |= INP_IPV4;
504 		error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
505 	}
506 	INP_HASH_WUNLOCK(&V_tcbinfo);
507 	if (error == 0) {
508 		tcp_state_change(tp, TCPS_LISTEN);
509 		solisten_proto(so, backlog);
510 #ifdef TCP_OFFLOAD
511 		if ((so->so_options & SO_NO_OFFLOAD) == 0)
512 			tcp_offload_listen_start(tp);
513 #endif
514 	}
515 	SOCK_UNLOCK(so);
516 
517 	if (IS_FASTOPEN(tp->t_flags))
518 		tp->t_tfo_pending = tcp_fastopen_alloc_counter();
519 
520 	if (error != 0)
521 		inp->inp_vflag = vflagsav;
522 
523 out:
524 	TCPDEBUG2(PRU_LISTEN);
525 	TCP_PROBE2(debug__user, tp, PRU_LISTEN);
526 	INP_WUNLOCK(inp);
527 	return (error);
528 }
529 #endif /* INET6 */
530 
531 #ifdef INET
532 /*
533  * Initiate connection to peer.
534  * Create a template for use in transmissions on this connection.
535  * Enter SYN_SENT state, and mark socket as connecting.
536  * Start keep-alive timer, and seed output sequence space.
537  * Send initial segment on connection.
538  */
539 static int
540 tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
541 {
542 	struct epoch_tracker et;
543 	int error = 0;
544 	struct inpcb *inp;
545 	struct tcpcb *tp = NULL;
546 	struct sockaddr_in *sinp;
547 
548 	sinp = (struct sockaddr_in *)nam;
549 	if (nam->sa_family != AF_INET)
550 		return (EAFNOSUPPORT);
551 	if (nam->sa_len != sizeof (*sinp))
552 		return (EINVAL);
553 
554 	/*
555 	 * Must disallow TCP ``connections'' to multicast addresses.
556 	 */
557 	if (IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
558 		return (EAFNOSUPPORT);
559 	if (ntohl(sinp->sin_addr.s_addr) == INADDR_BROADCAST)
560 		return (EACCES);
561 	if ((error = prison_remote_ip4(td->td_ucred, &sinp->sin_addr)) != 0)
562 		return (error);
563 
564 	TCPDEBUG0;
565 	inp = sotoinpcb(so);
566 	KASSERT(inp != NULL, ("tcp_usr_connect: inp == NULL"));
567 	INP_WLOCK(inp);
568 	if (inp->inp_flags & INP_TIMEWAIT) {
569 		error = EADDRINUSE;
570 		goto out;
571 	}
572 	if (inp->inp_flags & INP_DROPPED) {
573 		error = ECONNREFUSED;
574 		goto out;
575 	}
576 	tp = intotcpcb(inp);
577 	TCPDEBUG1();
578 	NET_EPOCH_ENTER(et);
579 	if ((error = tcp_connect(tp, nam, td)) != 0)
580 		goto out_in_epoch;
581 #ifdef TCP_OFFLOAD
582 	if (registered_toedevs > 0 &&
583 	    (so->so_options & SO_NO_OFFLOAD) == 0 &&
584 	    (error = tcp_offload_connect(so, nam)) == 0)
585 		goto out_in_epoch;
586 #endif
587 	tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
588 	error = tp->t_fb->tfb_tcp_output(tp);
589 out_in_epoch:
590 	NET_EPOCH_EXIT(et);
591 out:
592 	TCPDEBUG2(PRU_CONNECT);
593 	TCP_PROBE2(debug__user, tp, PRU_CONNECT);
594 	INP_WUNLOCK(inp);
595 	return (error);
596 }
597 #endif /* INET */
598 
599 #ifdef INET6
600 static int
601 tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
602 {
603 	struct epoch_tracker et;
604 	int error = 0;
605 	struct inpcb *inp;
606 	struct tcpcb *tp = NULL;
607 	struct sockaddr_in6 *sin6;
608 	u_int8_t incflagsav;
609 	u_char vflagsav;
610 
611 	TCPDEBUG0;
612 
613 	sin6 = (struct sockaddr_in6 *)nam;
614 	if (nam->sa_family != AF_INET6)
615 		return (EAFNOSUPPORT);
616 	if (nam->sa_len != sizeof (*sin6))
617 		return (EINVAL);
618 
619 	/*
620 	 * Must disallow TCP ``connections'' to multicast addresses.
621 	 */
622 	if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
623 		return (EAFNOSUPPORT);
624 
625 	inp = sotoinpcb(so);
626 	KASSERT(inp != NULL, ("tcp6_usr_connect: inp == NULL"));
627 	INP_WLOCK(inp);
628 	vflagsav = inp->inp_vflag;
629 	incflagsav = inp->inp_inc.inc_flags;
630 	if (inp->inp_flags & INP_TIMEWAIT) {
631 		error = EADDRINUSE;
632 		goto out;
633 	}
634 	if (inp->inp_flags & INP_DROPPED) {
635 		error = ECONNREFUSED;
636 		goto out;
637 	}
638 	tp = intotcpcb(inp);
639 	TCPDEBUG1();
640 #ifdef INET
641 	/*
642 	 * XXXRW: Some confusion: V4/V6 flags relate to binding, and
643 	 * therefore probably require the hash lock, which isn't held here.
644 	 * Is this a significant problem?
645 	 */
646 	if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
647 		struct sockaddr_in sin;
648 
649 		if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
650 			error = EINVAL;
651 			goto out;
652 		}
653 		if ((inp->inp_vflag & INP_IPV4) == 0) {
654 			error = EAFNOSUPPORT;
655 			goto out;
656 		}
657 
658 		in6_sin6_2_sin(&sin, sin6);
659 		if (IN_MULTICAST(ntohl(sin.sin_addr.s_addr))) {
660 			error = EAFNOSUPPORT;
661 			goto out;
662 		}
663 		if (ntohl(sin.sin_addr.s_addr) == INADDR_BROADCAST) {
664 			error = EACCES;
665 			goto out;
666 		}
667 		if ((error = prison_remote_ip4(td->td_ucred,
668 		    &sin.sin_addr)) != 0)
669 			goto out;
670 		inp->inp_vflag |= INP_IPV4;
671 		inp->inp_vflag &= ~INP_IPV6;
672 		NET_EPOCH_ENTER(et);
673 		if ((error = tcp_connect(tp, (struct sockaddr *)&sin, td)) != 0)
674 			goto out_in_epoch;
675 #ifdef TCP_OFFLOAD
676 		if (registered_toedevs > 0 &&
677 		    (so->so_options & SO_NO_OFFLOAD) == 0 &&
678 		    (error = tcp_offload_connect(so, nam)) == 0)
679 			goto out_in_epoch;
680 #endif
681 		error = tp->t_fb->tfb_tcp_output(tp);
682 		goto out_in_epoch;
683 	} else {
684 		if ((inp->inp_vflag & INP_IPV6) == 0) {
685 			error = EAFNOSUPPORT;
686 			goto out;
687 		}
688 	}
689 #endif
690 	if ((error = prison_remote_ip6(td->td_ucred, &sin6->sin6_addr)) != 0)
691 		goto out;
692 	inp->inp_vflag &= ~INP_IPV4;
693 	inp->inp_vflag |= INP_IPV6;
694 	inp->inp_inc.inc_flags |= INC_ISIPV6;
695 	if ((error = tcp6_connect(tp, nam, td)) != 0)
696 		goto out;
697 #ifdef TCP_OFFLOAD
698 	if (registered_toedevs > 0 &&
699 	    (so->so_options & SO_NO_OFFLOAD) == 0 &&
700 	    (error = tcp_offload_connect(so, nam)) == 0)
701 		goto out;
702 #endif
703 	tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
704 	NET_EPOCH_ENTER(et);
705 	error = tp->t_fb->tfb_tcp_output(tp);
706 #ifdef INET
707 out_in_epoch:
708 #endif
709 	NET_EPOCH_EXIT(et);
710 out:
711 	/*
712 	 * If the implicit bind in the connect call fails, restore
713 	 * the flags we modified.
714 	 */
715 	if (error != 0 && inp->inp_lport == 0) {
716 		inp->inp_vflag = vflagsav;
717 		inp->inp_inc.inc_flags = incflagsav;
718 	}
719 
720 	TCPDEBUG2(PRU_CONNECT);
721 	TCP_PROBE2(debug__user, tp, PRU_CONNECT);
722 	INP_WUNLOCK(inp);
723 	return (error);
724 }
725 #endif /* INET6 */
726 
727 /*
728  * Initiate disconnect from peer.
729  * If connection never passed embryonic stage, just drop;
730  * else if don't need to let data drain, then can just drop anyways,
731  * else have to begin TCP shutdown process: mark socket disconnecting,
732  * drain unread data, state switch to reflect user close, and
733  * send segment (e.g. FIN) to peer.  Socket will be really disconnected
734  * when peer sends FIN and acks ours.
735  *
736  * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.
737  */
738 static int
739 tcp_usr_disconnect(struct socket *so)
740 {
741 	struct inpcb *inp;
742 	struct tcpcb *tp = NULL;
743 	struct epoch_tracker et;
744 	int error = 0;
745 
746 	TCPDEBUG0;
747 	NET_EPOCH_ENTER(et);
748 	inp = sotoinpcb(so);
749 	KASSERT(inp != NULL, ("tcp_usr_disconnect: inp == NULL"));
750 	INP_WLOCK(inp);
751 	if (inp->inp_flags & INP_TIMEWAIT)
752 		goto out;
753 	if (inp->inp_flags & INP_DROPPED) {
754 		error = ECONNRESET;
755 		goto out;
756 	}
757 	tp = intotcpcb(inp);
758 	TCPDEBUG1();
759 	tcp_disconnect(tp);
760 out:
761 	TCPDEBUG2(PRU_DISCONNECT);
762 	TCP_PROBE2(debug__user, tp, PRU_DISCONNECT);
763 	INP_WUNLOCK(inp);
764 	NET_EPOCH_EXIT(et);
765 	return (error);
766 }
767 
768 #ifdef INET
769 /*
770  * Accept a connection.  Essentially all the work is done at higher levels;
771  * just return the address of the peer, storing through addr.
772  */
773 static int
774 tcp_usr_accept(struct socket *so, struct sockaddr **nam)
775 {
776 	int error = 0;
777 	struct inpcb *inp = NULL;
778 	struct tcpcb *tp = NULL;
779 	struct in_addr addr;
780 	in_port_t port = 0;
781 	TCPDEBUG0;
782 
783 	if (so->so_state & SS_ISDISCONNECTED)
784 		return (ECONNABORTED);
785 
786 	inp = sotoinpcb(so);
787 	KASSERT(inp != NULL, ("tcp_usr_accept: inp == NULL"));
788 	INP_WLOCK(inp);
789 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
790 		error = ECONNABORTED;
791 		goto out;
792 	}
793 	tp = intotcpcb(inp);
794 	TCPDEBUG1();
795 
796 	/*
797 	 * We inline in_getpeeraddr and COMMON_END here, so that we can
798 	 * copy the data of interest and defer the malloc until after we
799 	 * release the lock.
800 	 */
801 	port = inp->inp_fport;
802 	addr = inp->inp_faddr;
803 
804 out:
805 	TCPDEBUG2(PRU_ACCEPT);
806 	TCP_PROBE2(debug__user, tp, PRU_ACCEPT);
807 	INP_WUNLOCK(inp);
808 	if (error == 0)
809 		*nam = in_sockaddr(port, &addr);
810 	return error;
811 }
812 #endif /* INET */
813 
814 #ifdef INET6
815 static int
816 tcp6_usr_accept(struct socket *so, struct sockaddr **nam)
817 {
818 	struct inpcb *inp = NULL;
819 	int error = 0;
820 	struct tcpcb *tp = NULL;
821 	struct in_addr addr;
822 	struct in6_addr addr6;
823 	struct epoch_tracker et;
824 	in_port_t port = 0;
825 	int v4 = 0;
826 	TCPDEBUG0;
827 
828 	if (so->so_state & SS_ISDISCONNECTED)
829 		return (ECONNABORTED);
830 
831 	inp = sotoinpcb(so);
832 	KASSERT(inp != NULL, ("tcp6_usr_accept: inp == NULL"));
833 	NET_EPOCH_ENTER(et);
834 	INP_WLOCK(inp);
835 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
836 		error = ECONNABORTED;
837 		goto out;
838 	}
839 	tp = intotcpcb(inp);
840 	TCPDEBUG1();
841 
842 	/*
843 	 * We inline in6_mapped_peeraddr and COMMON_END here, so that we can
844 	 * copy the data of interest and defer the malloc until after we
845 	 * release the lock.
846 	 */
847 	if (inp->inp_vflag & INP_IPV4) {
848 		v4 = 1;
849 		port = inp->inp_fport;
850 		addr = inp->inp_faddr;
851 	} else {
852 		port = inp->inp_fport;
853 		addr6 = inp->in6p_faddr;
854 	}
855 
856 out:
857 	TCPDEBUG2(PRU_ACCEPT);
858 	TCP_PROBE2(debug__user, tp, PRU_ACCEPT);
859 	INP_WUNLOCK(inp);
860 	NET_EPOCH_EXIT(et);
861 	if (error == 0) {
862 		if (v4)
863 			*nam = in6_v4mapsin6_sockaddr(port, &addr);
864 		else
865 			*nam = in6_sockaddr(port, &addr6);
866 	}
867 	return error;
868 }
869 #endif /* INET6 */
870 
871 /*
872  * Mark the connection as being incapable of further output.
873  */
874 static int
875 tcp_usr_shutdown(struct socket *so)
876 {
877 	int error = 0;
878 	struct inpcb *inp;
879 	struct tcpcb *tp = NULL;
880 	struct epoch_tracker et;
881 
882 	TCPDEBUG0;
883 	NET_EPOCH_ENTER(et);
884 	inp = sotoinpcb(so);
885 	KASSERT(inp != NULL, ("inp == NULL"));
886 	INP_WLOCK(inp);
887 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
888 		error = ECONNRESET;
889 		goto out;
890 	}
891 	tp = intotcpcb(inp);
892 	TCPDEBUG1();
893 	socantsendmore(so);
894 	tcp_usrclosed(tp);
895 	if (!(inp->inp_flags & INP_DROPPED))
896 		error = tp->t_fb->tfb_tcp_output(tp);
897 
898 out:
899 	TCPDEBUG2(PRU_SHUTDOWN);
900 	TCP_PROBE2(debug__user, tp, PRU_SHUTDOWN);
901 	INP_WUNLOCK(inp);
902 	NET_EPOCH_EXIT(et);
903 
904 	return (error);
905 }
906 
907 /*
908  * After a receive, possibly send window update to peer.
909  */
910 static int
911 tcp_usr_rcvd(struct socket *so, int flags)
912 {
913 	struct epoch_tracker et;
914 	struct inpcb *inp;
915 	struct tcpcb *tp = NULL;
916 	int error = 0;
917 
918 	TCPDEBUG0;
919 	inp = sotoinpcb(so);
920 	KASSERT(inp != NULL, ("tcp_usr_rcvd: inp == NULL"));
921 	INP_WLOCK(inp);
922 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
923 		error = ECONNRESET;
924 		goto out;
925 	}
926 	tp = intotcpcb(inp);
927 	TCPDEBUG1();
928 	/*
929 	 * For passively-created TFO connections, don't attempt a window
930 	 * update while still in SYN_RECEIVED as this may trigger an early
931 	 * SYN|ACK.  It is preferable to have the SYN|ACK be sent along with
932 	 * application response data, or failing that, when the DELACK timer
933 	 * expires.
934 	 */
935 	if (IS_FASTOPEN(tp->t_flags) &&
936 	    (tp->t_state == TCPS_SYN_RECEIVED))
937 		goto out;
938 	NET_EPOCH_ENTER(et);
939 #ifdef TCP_OFFLOAD
940 	if (tp->t_flags & TF_TOE)
941 		tcp_offload_rcvd(tp);
942 	else
943 #endif
944 	tp->t_fb->tfb_tcp_output(tp);
945 	NET_EPOCH_EXIT(et);
946 out:
947 	TCPDEBUG2(PRU_RCVD);
948 	TCP_PROBE2(debug__user, tp, PRU_RCVD);
949 	INP_WUNLOCK(inp);
950 	return (error);
951 }
952 
953 /*
954  * Do a send by putting data in output queue and updating urgent
955  * marker if URG set.  Possibly send more data.  Unlike the other
956  * pru_*() routines, the mbuf chains are our responsibility.  We
957  * must either enqueue them or free them.  The other pru_* routines
958  * generally are caller-frees.
959  */
960 static int
961 tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
962     struct sockaddr *nam, struct mbuf *control, struct thread *td)
963 {
964 	struct epoch_tracker et;
965 	int error = 0;
966 	struct inpcb *inp;
967 	struct tcpcb *tp = NULL;
968 #ifdef INET
969 #ifdef INET6
970 	struct sockaddr_in sin;
971 #endif
972 	struct sockaddr_in *sinp;
973 #endif
974 #ifdef INET6
975 	int isipv6;
976 #endif
977 	u_int8_t incflagsav;
978 	u_char vflagsav;
979 	bool restoreflags;
980 	TCPDEBUG0;
981 
982 	/*
983 	 * We require the pcbinfo "read lock" if we will close the socket
984 	 * as part of this call.
985 	 */
986 	NET_EPOCH_ENTER(et);
987 	inp = sotoinpcb(so);
988 	KASSERT(inp != NULL, ("tcp_usr_send: inp == NULL"));
989 	INP_WLOCK(inp);
990 	vflagsav = inp->inp_vflag;
991 	incflagsav = inp->inp_inc.inc_flags;
992 	restoreflags = false;
993 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
994 		if (control)
995 			m_freem(control);
996 		error = ECONNRESET;
997 		goto out;
998 	}
999 	if (control != NULL) {
1000 		/* TCP doesn't do control messages (rights, creds, etc) */
1001 		if (control->m_len) {
1002 			m_freem(control);
1003 			error = EINVAL;
1004 			goto out;
1005 		}
1006 		m_freem(control);	/* empty control, just free it */
1007 		control = NULL;
1008 	}
1009 	tp = intotcpcb(inp);
1010 	if ((flags & PRUS_OOB) != 0 &&
1011 	    (error = tcp_pru_options_support(tp, PRUS_OOB)) != 0)
1012 		goto out;
1013 
1014 	TCPDEBUG1();
1015 	if (nam != NULL && tp->t_state < TCPS_SYN_SENT) {
1016 		switch (nam->sa_family) {
1017 #ifdef INET
1018 		case AF_INET:
1019 			sinp = (struct sockaddr_in *)nam;
1020 			if (sinp->sin_len != sizeof(struct sockaddr_in)) {
1021 				error = EINVAL;
1022 				goto out;
1023 			}
1024 			if ((inp->inp_vflag & INP_IPV6) != 0) {
1025 				error = EAFNOSUPPORT;
1026 				goto out;
1027 			}
1028 			if (IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) {
1029 				error = EAFNOSUPPORT;
1030 				goto out;
1031 			}
1032 			if (ntohl(sinp->sin_addr.s_addr) == INADDR_BROADCAST) {
1033 				error = EACCES;
1034 				goto out;
1035 			}
1036 			if ((error = prison_remote_ip4(td->td_ucred,
1037 			    &sinp->sin_addr)))
1038 				goto out;
1039 #ifdef INET6
1040 			isipv6 = 0;
1041 #endif
1042 			break;
1043 #endif /* INET */
1044 #ifdef INET6
1045 		case AF_INET6:
1046 		{
1047 			struct sockaddr_in6 *sin6;
1048 
1049 			sin6 = (struct sockaddr_in6 *)nam;
1050 			if (sin6->sin6_len != sizeof(*sin6)) {
1051 				error = EINVAL;
1052 				goto out;
1053 			}
1054 			if ((inp->inp_vflag & INP_IPV6PROTO) == 0) {
1055 				error = EAFNOSUPPORT;
1056 				goto out;
1057 			}
1058 			if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) {
1059 				error = EAFNOSUPPORT;
1060 				goto out;
1061 			}
1062 			if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
1063 #ifdef INET
1064 				if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
1065 					error = EINVAL;
1066 					goto out;
1067 				}
1068 				if ((inp->inp_vflag & INP_IPV4) == 0) {
1069 					error = EAFNOSUPPORT;
1070 					goto out;
1071 				}
1072 				restoreflags = true;
1073 				inp->inp_vflag &= ~INP_IPV6;
1074 				sinp = &sin;
1075 				in6_sin6_2_sin(sinp, sin6);
1076 				if (IN_MULTICAST(
1077 				    ntohl(sinp->sin_addr.s_addr))) {
1078 					error = EAFNOSUPPORT;
1079 					goto out;
1080 				}
1081 				if ((error = prison_remote_ip4(td->td_ucred,
1082 				    &sinp->sin_addr)))
1083 					goto out;
1084 				isipv6 = 0;
1085 #else /* !INET */
1086 				error = EAFNOSUPPORT;
1087 				goto out;
1088 #endif /* INET */
1089 			} else {
1090 				if ((inp->inp_vflag & INP_IPV6) == 0) {
1091 					error = EAFNOSUPPORT;
1092 					goto out;
1093 				}
1094 				restoreflags = true;
1095 				inp->inp_vflag &= ~INP_IPV4;
1096 				inp->inp_inc.inc_flags |= INC_ISIPV6;
1097 				if ((error = prison_remote_ip6(td->td_ucred,
1098 				    &sin6->sin6_addr)))
1099 					goto out;
1100 				isipv6 = 1;
1101 			}
1102 			break;
1103 		}
1104 #endif /* INET6 */
1105 		default:
1106 			error = EAFNOSUPPORT;
1107 			goto out;
1108 		}
1109 	}
1110 	if (!(flags & PRUS_OOB)) {
1111 		sbappendstream(&so->so_snd, m, flags);
1112 		m = NULL;
1113 		if (nam && tp->t_state < TCPS_SYN_SENT) {
1114 			/*
1115 			 * Do implied connect if not yet connected,
1116 			 * initialize window to default value, and
1117 			 * initialize maxseg using peer's cached MSS.
1118 			 */
1119 #ifdef INET6
1120 			if (isipv6)
1121 				error = tcp6_connect(tp, nam, td);
1122 #endif /* INET6 */
1123 #if defined(INET6) && defined(INET)
1124 			else
1125 #endif
1126 #ifdef INET
1127 				error = tcp_connect(tp,
1128 				    (struct sockaddr *)sinp, td);
1129 #endif
1130 			/*
1131 			 * The bind operation in tcp_connect succeeded. We
1132 			 * no longer want to restore the flags if later
1133 			 * operations fail.
1134 			 */
1135 			if (error == 0 || inp->inp_lport != 0)
1136 				restoreflags = false;
1137 
1138 			if (error) {
1139 				/* m is freed if PRUS_NOTREADY is unset. */
1140 				sbflush(&so->so_snd);
1141 				goto out;
1142 			}
1143 			if (IS_FASTOPEN(tp->t_flags))
1144 				tcp_fastopen_connect(tp);
1145 			else {
1146 				tp->snd_wnd = TTCP_CLIENT_SND_WND;
1147 				tcp_mss(tp, -1);
1148 			}
1149 		}
1150 		if (flags & PRUS_EOF) {
1151 			/*
1152 			 * Close the send side of the connection after
1153 			 * the data is sent.
1154 			 */
1155 			socantsendmore(so);
1156 			tcp_usrclosed(tp);
1157 		}
1158 		if (TCPS_HAVEESTABLISHED(tp->t_state) &&
1159 		    ((tp->t_flags2 & TF2_FBYTES_COMPLETE) == 0) &&
1160 		    (tp->t_fbyte_out == 0) &&
1161 		    (so->so_snd.sb_ccc > 0)) {
1162 			tp->t_fbyte_out = ticks;
1163 			if (tp->t_fbyte_out == 0)
1164 				tp->t_fbyte_out = 1;
1165 			if (tp->t_fbyte_out && tp->t_fbyte_in)
1166 				tp->t_flags2 |= TF2_FBYTES_COMPLETE;
1167 		}
1168 		if (!(inp->inp_flags & INP_DROPPED) &&
1169 		    !(flags & PRUS_NOTREADY)) {
1170 			if (flags & PRUS_MORETOCOME)
1171 				tp->t_flags |= TF_MORETOCOME;
1172 			error = tp->t_fb->tfb_tcp_output(tp);
1173 			if (flags & PRUS_MORETOCOME)
1174 				tp->t_flags &= ~TF_MORETOCOME;
1175 		}
1176 	} else {
1177 		/*
1178 		 * XXXRW: PRUS_EOF not implemented with PRUS_OOB?
1179 		 */
1180 		SOCKBUF_LOCK(&so->so_snd);
1181 		if (sbspace(&so->so_snd) < -512) {
1182 			SOCKBUF_UNLOCK(&so->so_snd);
1183 			error = ENOBUFS;
1184 			goto out;
1185 		}
1186 		/*
1187 		 * According to RFC961 (Assigned Protocols),
1188 		 * the urgent pointer points to the last octet
1189 		 * of urgent data.  We continue, however,
1190 		 * to consider it to indicate the first octet
1191 		 * of data past the urgent section.
1192 		 * Otherwise, snd_up should be one lower.
1193 		 */
1194 		sbappendstream_locked(&so->so_snd, m, flags);
1195 		SOCKBUF_UNLOCK(&so->so_snd);
1196 		m = NULL;
1197 		if (nam && tp->t_state < TCPS_SYN_SENT) {
1198 			/*
1199 			 * Do implied connect if not yet connected,
1200 			 * initialize window to default value, and
1201 			 * initialize maxseg using peer's cached MSS.
1202 			 */
1203 
1204 			/*
1205 			 * Not going to contemplate SYN|URG
1206 			 */
1207 			if (IS_FASTOPEN(tp->t_flags))
1208 				tp->t_flags &= ~TF_FASTOPEN;
1209 #ifdef INET6
1210 			if (isipv6)
1211 				error = tcp6_connect(tp, nam, td);
1212 #endif /* INET6 */
1213 #if defined(INET6) && defined(INET)
1214 			else
1215 #endif
1216 #ifdef INET
1217 				error = tcp_connect(tp,
1218 				    (struct sockaddr *)sinp, td);
1219 #endif
1220 			/*
1221 			 * The bind operation in tcp_connect succeeded. We
1222 			 * no longer want to restore the flags if later
1223 			 * operations fail.
1224 			 */
1225 			if (error == 0 || inp->inp_lport != 0)
1226 				restoreflags = false;
1227 
1228 			if (error != 0) {
1229 				/* m is freed if PRUS_NOTREADY is unset. */
1230 				sbflush(&so->so_snd);
1231 				goto out;
1232 			}
1233 			tp->snd_wnd = TTCP_CLIENT_SND_WND;
1234 			tcp_mss(tp, -1);
1235 		}
1236 		tp->snd_up = tp->snd_una + sbavail(&so->so_snd);
1237 		if ((flags & PRUS_NOTREADY) == 0) {
1238 			tp->t_flags |= TF_FORCEDATA;
1239 			error = tp->t_fb->tfb_tcp_output(tp);
1240 			tp->t_flags &= ~TF_FORCEDATA;
1241 		}
1242 	}
1243 	TCP_LOG_EVENT(tp, NULL,
1244 	    &inp->inp_socket->so_rcv,
1245 	    &inp->inp_socket->so_snd,
1246 	    TCP_LOG_USERSEND, error,
1247 	    0, NULL, false);
1248 
1249 out:
1250 	/*
1251 	 * In case of PRUS_NOTREADY, the caller or tcp_usr_ready() is
1252 	 * responsible for freeing memory.
1253 	 */
1254 	if (m != NULL && (flags & PRUS_NOTREADY) == 0)
1255 		m_freem(m);
1256 
1257 	/*
1258 	 * If the request was unsuccessful and we changed flags,
1259 	 * restore the original flags.
1260 	 */
1261 	if (error != 0 && restoreflags) {
1262 		inp->inp_vflag = vflagsav;
1263 		inp->inp_inc.inc_flags = incflagsav;
1264 	}
1265 	TCPDEBUG2((flags & PRUS_OOB) ? PRU_SENDOOB :
1266 		  ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
1267 	TCP_PROBE2(debug__user, tp, (flags & PRUS_OOB) ? PRU_SENDOOB :
1268 		   ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
1269 	INP_WUNLOCK(inp);
1270 	NET_EPOCH_EXIT(et);
1271 	return (error);
1272 }
1273 
1274 static int
1275 tcp_usr_ready(struct socket *so, struct mbuf *m, int count)
1276 {
1277 	struct epoch_tracker et;
1278 	struct inpcb *inp;
1279 	struct tcpcb *tp;
1280 	int error;
1281 
1282 	inp = sotoinpcb(so);
1283 	INP_WLOCK(inp);
1284 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1285 		INP_WUNLOCK(inp);
1286 		mb_free_notready(m, count);
1287 		return (ECONNRESET);
1288 	}
1289 	tp = intotcpcb(inp);
1290 
1291 	SOCKBUF_LOCK(&so->so_snd);
1292 	error = sbready(&so->so_snd, m, count);
1293 	SOCKBUF_UNLOCK(&so->so_snd);
1294 	if (error == 0) {
1295 		NET_EPOCH_ENTER(et);
1296 		error = tp->t_fb->tfb_tcp_output(tp);
1297 		NET_EPOCH_EXIT(et);
1298 	}
1299 	INP_WUNLOCK(inp);
1300 
1301 	return (error);
1302 }
1303 
1304 /*
1305  * Abort the TCP.  Drop the connection abruptly.
1306  */
1307 static void
1308 tcp_usr_abort(struct socket *so)
1309 {
1310 	struct inpcb *inp;
1311 	struct tcpcb *tp = NULL;
1312 	struct epoch_tracker et;
1313 	TCPDEBUG0;
1314 
1315 	inp = sotoinpcb(so);
1316 	KASSERT(inp != NULL, ("tcp_usr_abort: inp == NULL"));
1317 
1318 	NET_EPOCH_ENTER(et);
1319 	INP_WLOCK(inp);
1320 	KASSERT(inp->inp_socket != NULL,
1321 	    ("tcp_usr_abort: inp_socket == NULL"));
1322 
1323 	/*
1324 	 * If we still have full TCP state, and we're not dropped, drop.
1325 	 */
1326 	if (!(inp->inp_flags & INP_TIMEWAIT) &&
1327 	    !(inp->inp_flags & INP_DROPPED)) {
1328 		tp = intotcpcb(inp);
1329 		TCPDEBUG1();
1330 		tp = tcp_drop(tp, ECONNABORTED);
1331 		if (tp == NULL)
1332 			goto dropped;
1333 		TCPDEBUG2(PRU_ABORT);
1334 		TCP_PROBE2(debug__user, tp, PRU_ABORT);
1335 	}
1336 	if (!(inp->inp_flags & INP_DROPPED)) {
1337 		SOCK_LOCK(so);
1338 		so->so_state |= SS_PROTOREF;
1339 		SOCK_UNLOCK(so);
1340 		inp->inp_flags |= INP_SOCKREF;
1341 	}
1342 	INP_WUNLOCK(inp);
1343 dropped:
1344 	NET_EPOCH_EXIT(et);
1345 }
1346 
1347 /*
1348  * TCP socket is closed.  Start friendly disconnect.
1349  */
1350 static void
1351 tcp_usr_close(struct socket *so)
1352 {
1353 	struct inpcb *inp;
1354 	struct tcpcb *tp = NULL;
1355 	struct epoch_tracker et;
1356 	TCPDEBUG0;
1357 
1358 	inp = sotoinpcb(so);
1359 	KASSERT(inp != NULL, ("tcp_usr_close: inp == NULL"));
1360 
1361 	NET_EPOCH_ENTER(et);
1362 	INP_WLOCK(inp);
1363 	KASSERT(inp->inp_socket != NULL,
1364 	    ("tcp_usr_close: inp_socket == NULL"));
1365 
1366 	/*
1367 	 * If we still have full TCP state, and we're not dropped, initiate
1368 	 * a disconnect.
1369 	 */
1370 	if (!(inp->inp_flags & INP_TIMEWAIT) &&
1371 	    !(inp->inp_flags & INP_DROPPED)) {
1372 		tp = intotcpcb(inp);
1373 		TCPDEBUG1();
1374 		tcp_disconnect(tp);
1375 		TCPDEBUG2(PRU_CLOSE);
1376 		TCP_PROBE2(debug__user, tp, PRU_CLOSE);
1377 	}
1378 	if (!(inp->inp_flags & INP_DROPPED)) {
1379 		SOCK_LOCK(so);
1380 		so->so_state |= SS_PROTOREF;
1381 		SOCK_UNLOCK(so);
1382 		inp->inp_flags |= INP_SOCKREF;
1383 	}
1384 	INP_WUNLOCK(inp);
1385 	NET_EPOCH_EXIT(et);
1386 }
1387 
1388 static int
1389 tcp_pru_options_support(struct tcpcb *tp, int flags)
1390 {
1391 	/*
1392 	 * If the specific TCP stack has a pru_options
1393 	 * specified then it does not always support
1394 	 * all the PRU_XX options and we must ask it.
1395 	 * If the function is not specified then all
1396 	 * of the PRU_XX options are supported.
1397 	 */
1398 	int ret = 0;
1399 
1400 	if (tp->t_fb->tfb_pru_options) {
1401 		ret = (*tp->t_fb->tfb_pru_options)(tp, flags);
1402 	}
1403 	return (ret);
1404 }
1405 
1406 /*
1407  * Receive out-of-band data.
1408  */
1409 static int
1410 tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags)
1411 {
1412 	int error = 0;
1413 	struct inpcb *inp;
1414 	struct tcpcb *tp = NULL;
1415 
1416 	TCPDEBUG0;
1417 	inp = sotoinpcb(so);
1418 	KASSERT(inp != NULL, ("tcp_usr_rcvoob: inp == NULL"));
1419 	INP_WLOCK(inp);
1420 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1421 		error = ECONNRESET;
1422 		goto out;
1423 	}
1424 	tp = intotcpcb(inp);
1425 	error = tcp_pru_options_support(tp, PRUS_OOB);
1426 	if (error) {
1427 		goto out;
1428 	}
1429 	TCPDEBUG1();
1430 	if ((so->so_oobmark == 0 &&
1431 	     (so->so_rcv.sb_state & SBS_RCVATMARK) == 0) ||
1432 	    so->so_options & SO_OOBINLINE ||
1433 	    tp->t_oobflags & TCPOOB_HADDATA) {
1434 		error = EINVAL;
1435 		goto out;
1436 	}
1437 	if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
1438 		error = EWOULDBLOCK;
1439 		goto out;
1440 	}
1441 	m->m_len = 1;
1442 	*mtod(m, caddr_t) = tp->t_iobc;
1443 	if ((flags & MSG_PEEK) == 0)
1444 		tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
1445 
1446 out:
1447 	TCPDEBUG2(PRU_RCVOOB);
1448 	TCP_PROBE2(debug__user, tp, PRU_RCVOOB);
1449 	INP_WUNLOCK(inp);
1450 	return (error);
1451 }
1452 
1453 #ifdef INET
1454 struct pr_usrreqs tcp_usrreqs = {
1455 	.pru_abort =		tcp_usr_abort,
1456 	.pru_accept =		tcp_usr_accept,
1457 	.pru_attach =		tcp_usr_attach,
1458 	.pru_bind =		tcp_usr_bind,
1459 	.pru_connect =		tcp_usr_connect,
1460 	.pru_control =		in_control,
1461 	.pru_detach =		tcp_usr_detach,
1462 	.pru_disconnect =	tcp_usr_disconnect,
1463 	.pru_listen =		tcp_usr_listen,
1464 	.pru_peeraddr =		in_getpeeraddr,
1465 	.pru_rcvd =		tcp_usr_rcvd,
1466 	.pru_rcvoob =		tcp_usr_rcvoob,
1467 	.pru_send =		tcp_usr_send,
1468 	.pru_ready =		tcp_usr_ready,
1469 	.pru_shutdown =		tcp_usr_shutdown,
1470 	.pru_sockaddr =		in_getsockaddr,
1471 	.pru_sosetlabel =	in_pcbsosetlabel,
1472 	.pru_close =		tcp_usr_close,
1473 };
1474 #endif /* INET */
1475 
1476 #ifdef INET6
1477 struct pr_usrreqs tcp6_usrreqs = {
1478 	.pru_abort =		tcp_usr_abort,
1479 	.pru_accept =		tcp6_usr_accept,
1480 	.pru_attach =		tcp_usr_attach,
1481 	.pru_bind =		tcp6_usr_bind,
1482 	.pru_connect =		tcp6_usr_connect,
1483 	.pru_control =		in6_control,
1484 	.pru_detach =		tcp_usr_detach,
1485 	.pru_disconnect =	tcp_usr_disconnect,
1486 	.pru_listen =		tcp6_usr_listen,
1487 	.pru_peeraddr =		in6_mapped_peeraddr,
1488 	.pru_rcvd =		tcp_usr_rcvd,
1489 	.pru_rcvoob =		tcp_usr_rcvoob,
1490 	.pru_send =		tcp_usr_send,
1491 	.pru_ready =		tcp_usr_ready,
1492 	.pru_shutdown =		tcp_usr_shutdown,
1493 	.pru_sockaddr =		in6_mapped_sockaddr,
1494 	.pru_sosetlabel =	in_pcbsosetlabel,
1495 	.pru_close =		tcp_usr_close,
1496 };
1497 #endif /* INET6 */
1498 
1499 #ifdef INET
1500 /*
1501  * Common subroutine to open a TCP connection to remote host specified
1502  * by struct sockaddr_in in mbuf *nam.  Call in_pcbbind to assign a local
1503  * port number if needed.  Call in_pcbconnect_setup to do the routing and
1504  * to choose a local host address (interface).  If there is an existing
1505  * incarnation of the same connection in TIME-WAIT state and if the remote
1506  * host was sending CC options and if the connection duration was < MSL, then
1507  * truncate the previous TIME-WAIT state and proceed.
1508  * Initialize connection parameters and enter SYN-SENT state.
1509  */
1510 static int
1511 tcp_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1512 {
1513 	struct inpcb *inp = tp->t_inpcb, *oinp;
1514 	struct socket *so = inp->inp_socket;
1515 	struct in_addr laddr;
1516 	u_short lport;
1517 	int error;
1518 
1519 	NET_EPOCH_ASSERT();
1520 	INP_WLOCK_ASSERT(inp);
1521 	INP_HASH_WLOCK(&V_tcbinfo);
1522 
1523 	if (V_tcp_require_unique_port && inp->inp_lport == 0) {
1524 		error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1525 		if (error)
1526 			goto out;
1527 	}
1528 
1529 	/*
1530 	 * Cannot simply call in_pcbconnect, because there might be an
1531 	 * earlier incarnation of this same connection still in
1532 	 * TIME_WAIT state, creating an ADDRINUSE error.
1533 	 */
1534 	laddr = inp->inp_laddr;
1535 	lport = inp->inp_lport;
1536 	error = in_pcbconnect_setup(inp, nam, &laddr.s_addr, &lport,
1537 	    &inp->inp_faddr.s_addr, &inp->inp_fport, &oinp, td->td_ucred);
1538 	if (error && oinp == NULL)
1539 		goto out;
1540 	if (oinp) {
1541 		error = EADDRINUSE;
1542 		goto out;
1543 	}
1544 	/* Handle initial bind if it hadn't been done in advance. */
1545 	if (inp->inp_lport == 0) {
1546 		inp->inp_lport = lport;
1547 		if (in_pcbinshash(inp) != 0) {
1548 			inp->inp_lport = 0;
1549 			error = EAGAIN;
1550 			goto out;
1551 		}
1552 	}
1553 	inp->inp_laddr = laddr;
1554 	in_pcbrehash(inp);
1555 	INP_HASH_WUNLOCK(&V_tcbinfo);
1556 
1557 	/*
1558 	 * Compute window scaling to request:
1559 	 * Scale to fit into sweet spot.  See tcp_syncache.c.
1560 	 * XXX: This should move to tcp_output().
1561 	 */
1562 	while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1563 	    (TCP_MAXWIN << tp->request_r_scale) < sb_max)
1564 		tp->request_r_scale++;
1565 
1566 	soisconnecting(so);
1567 	TCPSTAT_INC(tcps_connattempt);
1568 	tcp_state_change(tp, TCPS_SYN_SENT);
1569 	tp->iss = tcp_new_isn(&inp->inp_inc);
1570 	if (tp->t_flags & TF_REQ_TSTMP)
1571 		tp->ts_offset = tcp_new_ts_offset(&inp->inp_inc);
1572 	tcp_sendseqinit(tp);
1573 
1574 	return 0;
1575 
1576 out:
1577 	INP_HASH_WUNLOCK(&V_tcbinfo);
1578 	return (error);
1579 }
1580 #endif /* INET */
1581 
1582 #ifdef INET6
1583 static int
1584 tcp6_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1585 {
1586 	struct inpcb *inp = tp->t_inpcb;
1587 	int error;
1588 
1589 	INP_WLOCK_ASSERT(inp);
1590 	INP_HASH_WLOCK(&V_tcbinfo);
1591 
1592 	if (V_tcp_require_unique_port && inp->inp_lport == 0) {
1593 		error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1594 		if (error)
1595 			goto out;
1596 	}
1597 	error = in6_pcbconnect(inp, nam, td->td_ucred);
1598 	if (error != 0)
1599 		goto out;
1600 	INP_HASH_WUNLOCK(&V_tcbinfo);
1601 
1602 	/* Compute window scaling to request.  */
1603 	while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1604 	    (TCP_MAXWIN << tp->request_r_scale) < sb_max)
1605 		tp->request_r_scale++;
1606 
1607 	soisconnecting(inp->inp_socket);
1608 	TCPSTAT_INC(tcps_connattempt);
1609 	tcp_state_change(tp, TCPS_SYN_SENT);
1610 	tp->iss = tcp_new_isn(&inp->inp_inc);
1611 	if (tp->t_flags & TF_REQ_TSTMP)
1612 		tp->ts_offset = tcp_new_ts_offset(&inp->inp_inc);
1613 	tcp_sendseqinit(tp);
1614 
1615 	return 0;
1616 
1617 out:
1618 	INP_HASH_WUNLOCK(&V_tcbinfo);
1619 	return error;
1620 }
1621 #endif /* INET6 */
1622 
1623 /*
1624  * Export TCP internal state information via a struct tcp_info, based on the
1625  * Linux 2.6 API.  Not ABI compatible as our constants are mapped differently
1626  * (TCP state machine, etc).  We export all information using FreeBSD-native
1627  * constants -- for example, the numeric values for tcpi_state will differ
1628  * from Linux.
1629  */
1630 static void
1631 tcp_fill_info(struct tcpcb *tp, struct tcp_info *ti)
1632 {
1633 
1634 	INP_WLOCK_ASSERT(tp->t_inpcb);
1635 	bzero(ti, sizeof(*ti));
1636 
1637 	ti->tcpi_state = tp->t_state;
1638 	if ((tp->t_flags & TF_REQ_TSTMP) && (tp->t_flags & TF_RCVD_TSTMP))
1639 		ti->tcpi_options |= TCPI_OPT_TIMESTAMPS;
1640 	if (tp->t_flags & TF_SACK_PERMIT)
1641 		ti->tcpi_options |= TCPI_OPT_SACK;
1642 	if ((tp->t_flags & TF_REQ_SCALE) && (tp->t_flags & TF_RCVD_SCALE)) {
1643 		ti->tcpi_options |= TCPI_OPT_WSCALE;
1644 		ti->tcpi_snd_wscale = tp->snd_scale;
1645 		ti->tcpi_rcv_wscale = tp->rcv_scale;
1646 	}
1647 	if (tp->t_flags2 & TF2_ECN_PERMIT)
1648 		ti->tcpi_options |= TCPI_OPT_ECN;
1649 
1650 	ti->tcpi_rto = tp->t_rxtcur * tick;
1651 	ti->tcpi_last_data_recv = ((uint32_t)ticks - tp->t_rcvtime) * tick;
1652 	ti->tcpi_rtt = ((u_int64_t)tp->t_srtt * tick) >> TCP_RTT_SHIFT;
1653 	ti->tcpi_rttvar = ((u_int64_t)tp->t_rttvar * tick) >> TCP_RTTVAR_SHIFT;
1654 
1655 	ti->tcpi_snd_ssthresh = tp->snd_ssthresh;
1656 	ti->tcpi_snd_cwnd = tp->snd_cwnd;
1657 
1658 	/*
1659 	 * FreeBSD-specific extension fields for tcp_info.
1660 	 */
1661 	ti->tcpi_rcv_space = tp->rcv_wnd;
1662 	ti->tcpi_rcv_nxt = tp->rcv_nxt;
1663 	ti->tcpi_snd_wnd = tp->snd_wnd;
1664 	ti->tcpi_snd_bwnd = 0;		/* Unused, kept for compat. */
1665 	ti->tcpi_snd_nxt = tp->snd_nxt;
1666 	ti->tcpi_snd_mss = tp->t_maxseg;
1667 	ti->tcpi_rcv_mss = tp->t_maxseg;
1668 	ti->tcpi_snd_rexmitpack = tp->t_sndrexmitpack;
1669 	ti->tcpi_rcv_ooopack = tp->t_rcvoopack;
1670 	ti->tcpi_snd_zerowin = tp->t_sndzerowin;
1671 #ifdef TCP_OFFLOAD
1672 	if (tp->t_flags & TF_TOE) {
1673 		ti->tcpi_options |= TCPI_OPT_TOE;
1674 		tcp_offload_tcp_info(tp, ti);
1675 	}
1676 #endif
1677 }
1678 
1679 /*
1680  * tcp_ctloutput() must drop the inpcb lock before performing copyin on
1681  * socket option arguments.  When it re-acquires the lock after the copy, it
1682  * has to revalidate that the connection is still valid for the socket
1683  * option.
1684  */
1685 #define INP_WLOCK_RECHECK_CLEANUP(inp, cleanup) do {			\
1686 	INP_WLOCK(inp);							\
1687 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {		\
1688 		INP_WUNLOCK(inp);					\
1689 		cleanup;						\
1690 		return (ECONNRESET);					\
1691 	}								\
1692 	tp = intotcpcb(inp);						\
1693 } while(0)
1694 #define INP_WLOCK_RECHECK(inp) INP_WLOCK_RECHECK_CLEANUP((inp), /* noop */)
1695 
1696 int
1697 tcp_ctloutput(struct socket *so, struct sockopt *sopt)
1698 {
1699 	int	error;
1700 	struct	inpcb *inp;
1701 	struct	tcpcb *tp;
1702 	struct tcp_function_block *blk;
1703 	struct tcp_function_set fsn;
1704 
1705 	error = 0;
1706 	inp = sotoinpcb(so);
1707 	KASSERT(inp != NULL, ("tcp_ctloutput: inp == NULL"));
1708 	if (sopt->sopt_level != IPPROTO_TCP) {
1709 #ifdef INET6
1710 		if (inp->inp_vflag & INP_IPV6PROTO) {
1711 			error = ip6_ctloutput(so, sopt);
1712 			/*
1713 			 * In case of the IPV6_USE_MIN_MTU socket option,
1714 			 * the INC_IPV6MINMTU flag to announce a corresponding
1715 			 * MSS during the initial handshake.
1716 			 * If the TCP connection is not in the front states,
1717 			 * just reduce the MSS being used.
1718 			 * This avoids the sending of TCP segments which will
1719 			 * be fragmented at the IPv6 layer.
1720 			 */
1721 			if ((error == 0) &&
1722 			    (sopt->sopt_dir == SOPT_SET) &&
1723 			    (sopt->sopt_level == IPPROTO_IPV6) &&
1724 			    (sopt->sopt_name == IPV6_USE_MIN_MTU)) {
1725 				INP_WLOCK(inp);
1726 				if ((inp->inp_flags &
1727 				    (INP_TIMEWAIT | INP_DROPPED))) {
1728 					INP_WUNLOCK(inp);
1729 					return (ECONNRESET);
1730 				}
1731 				inp->inp_inc.inc_flags |= INC_IPV6MINMTU;
1732 				tp = intotcpcb(inp);
1733 				if ((tp->t_state >= TCPS_SYN_SENT) &&
1734 				    (inp->inp_inc.inc_flags & INC_ISIPV6)) {
1735 					struct ip6_pktopts *opt;
1736 
1737 					opt = inp->in6p_outputopts;
1738 					if ((opt != NULL) &&
1739 					    (opt->ip6po_minmtu ==
1740 					    IP6PO_MINMTU_ALL)) {
1741 						if (tp->t_maxseg > TCP6_MSS) {
1742 							tp->t_maxseg = TCP6_MSS;
1743 						}
1744 					}
1745 				}
1746 				INP_WUNLOCK(inp);
1747 			}
1748 		}
1749 #endif /* INET6 */
1750 #if defined(INET6) && defined(INET)
1751 		else
1752 #endif
1753 #ifdef INET
1754 		{
1755 			error = ip_ctloutput(so, sopt);
1756 		}
1757 #endif
1758 		return (error);
1759 	}
1760 	INP_WLOCK(inp);
1761 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1762 		INP_WUNLOCK(inp);
1763 		return (ECONNRESET);
1764 	}
1765 	tp = intotcpcb(inp);
1766 	/*
1767 	 * Protect the TCP option TCP_FUNCTION_BLK so
1768 	 * that a sub-function can *never* overwrite this.
1769 	 */
1770 	if ((sopt->sopt_dir == SOPT_SET) &&
1771 	    (sopt->sopt_name == TCP_FUNCTION_BLK)) {
1772 		INP_WUNLOCK(inp);
1773 		error = sooptcopyin(sopt, &fsn, sizeof fsn,
1774 		    sizeof fsn);
1775 		if (error)
1776 			return (error);
1777 		INP_WLOCK_RECHECK(inp);
1778 		blk = find_and_ref_tcp_functions(&fsn);
1779 		if (blk == NULL) {
1780 			INP_WUNLOCK(inp);
1781 			return (ENOENT);
1782 		}
1783 		if (tp->t_fb == blk) {
1784 			/* You already have this */
1785 			refcount_release(&blk->tfb_refcnt);
1786 			INP_WUNLOCK(inp);
1787 			return (0);
1788 		}
1789 		if (tp->t_state != TCPS_CLOSED) {
1790 			/*
1791 			 * The user has advanced the state
1792 			 * past the initial point, we may not
1793 			 * be able to switch.
1794 			 */
1795 			if (blk->tfb_tcp_handoff_ok != NULL) {
1796 				/*
1797 				 * Does the stack provide a
1798 				 * query mechanism, if so it may
1799 				 * still be possible?
1800 				 */
1801 				error = (*blk->tfb_tcp_handoff_ok)(tp);
1802 			} else
1803 				error = EINVAL;
1804 			if (error) {
1805 				refcount_release(&blk->tfb_refcnt);
1806 				INP_WUNLOCK(inp);
1807 				return(error);
1808 			}
1809 		}
1810 		if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) {
1811 			refcount_release(&blk->tfb_refcnt);
1812 			INP_WUNLOCK(inp);
1813 			return (ENOENT);
1814 		}
1815 		/*
1816 		 * Release the old refcnt, the
1817 		 * lookup acquired a ref on the
1818 		 * new one already.
1819 		 */
1820 		if (tp->t_fb->tfb_tcp_fb_fini) {
1821 			struct epoch_tracker et;
1822 			/*
1823 			 * Tell the stack to cleanup with 0 i.e.
1824 			 * the tcb is not going away.
1825 			 */
1826 			NET_EPOCH_ENTER(et);
1827 			(*tp->t_fb->tfb_tcp_fb_fini)(tp, 0);
1828 			NET_EPOCH_EXIT(et);
1829 		}
1830 #ifdef TCPHPTS
1831 		/* Assure that we are not on any hpts */
1832 		tcp_hpts_remove(tp->t_inpcb, HPTS_REMOVE_ALL);
1833 #endif
1834 		if (blk->tfb_tcp_fb_init) {
1835 			error = (*blk->tfb_tcp_fb_init)(tp);
1836 			if (error) {
1837 				refcount_release(&blk->tfb_refcnt);
1838 				if (tp->t_fb->tfb_tcp_fb_init) {
1839 					if((*tp->t_fb->tfb_tcp_fb_init)(tp) != 0)  {
1840 						/* Fall back failed, drop the connection */
1841 						INP_WUNLOCK(inp);
1842 						soabort(so);
1843 						return(error);
1844 					}
1845 				}
1846 				goto err_out;
1847 			}
1848 		}
1849 		refcount_release(&tp->t_fb->tfb_refcnt);
1850 		tp->t_fb = blk;
1851 #ifdef TCP_OFFLOAD
1852 		if (tp->t_flags & TF_TOE) {
1853 			tcp_offload_ctloutput(tp, sopt->sopt_dir,
1854 			     sopt->sopt_name);
1855 		}
1856 #endif
1857 err_out:
1858 		INP_WUNLOCK(inp);
1859 		return (error);
1860 	} else if ((sopt->sopt_dir == SOPT_GET) &&
1861 	    (sopt->sopt_name == TCP_FUNCTION_BLK)) {
1862 		strncpy(fsn.function_set_name, tp->t_fb->tfb_tcp_block_name,
1863 		    TCP_FUNCTION_NAME_LEN_MAX);
1864 		fsn.function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0';
1865 		fsn.pcbcnt = tp->t_fb->tfb_refcnt;
1866 		INP_WUNLOCK(inp);
1867 		error = sooptcopyout(sopt, &fsn, sizeof fsn);
1868 		return (error);
1869 	}
1870 	/* Pass in the INP locked, called must unlock it */
1871 	return (tp->t_fb->tfb_tcp_ctloutput(so, sopt, inp, tp));
1872 }
1873 
1874 /*
1875  * If this assert becomes untrue, we need to change the size of the buf
1876  * variable in tcp_default_ctloutput().
1877  */
1878 #ifdef CTASSERT
1879 CTASSERT(TCP_CA_NAME_MAX <= TCP_LOG_ID_LEN);
1880 CTASSERT(TCP_LOG_REASON_LEN <= TCP_LOG_ID_LEN);
1881 #endif
1882 
1883 #ifdef KERN_TLS
1884 static int
1885 copyin_tls_enable(struct sockopt *sopt, struct tls_enable *tls)
1886 {
1887 	struct tls_enable_v0 tls_v0;
1888 	int error;
1889 
1890 	if (sopt->sopt_valsize == sizeof(tls_v0)) {
1891 		error = sooptcopyin(sopt, &tls_v0, sizeof(tls_v0),
1892 		    sizeof(tls_v0));
1893 		if (error)
1894 			return (error);
1895 		memset(tls, 0, sizeof(*tls));
1896 		tls->cipher_key = tls_v0.cipher_key;
1897 		tls->iv = tls_v0.iv;
1898 		tls->auth_key = tls_v0.auth_key;
1899 		tls->cipher_algorithm = tls_v0.cipher_algorithm;
1900 		tls->cipher_key_len = tls_v0.cipher_key_len;
1901 		tls->iv_len = tls_v0.iv_len;
1902 		tls->auth_algorithm = tls_v0.auth_algorithm;
1903 		tls->auth_key_len = tls_v0.auth_key_len;
1904 		tls->flags = tls_v0.flags;
1905 		tls->tls_vmajor = tls_v0.tls_vmajor;
1906 		tls->tls_vminor = tls_v0.tls_vminor;
1907 		return (0);
1908 	}
1909 
1910 	return (sooptcopyin(sopt, tls, sizeof(*tls), sizeof(*tls)));
1911 }
1912 #endif
1913 
1914 int
1915 tcp_default_ctloutput(struct socket *so, struct sockopt *sopt, struct inpcb *inp, struct tcpcb *tp)
1916 {
1917 	int	error, opt, optval;
1918 	u_int	ui;
1919 	struct	tcp_info ti;
1920 #ifdef KERN_TLS
1921 	struct tls_enable tls;
1922 #endif
1923 	struct cc_algo *algo;
1924 	char	*pbuf, buf[TCP_LOG_ID_LEN];
1925 #ifdef STATS
1926 	struct statsblob *sbp;
1927 #endif
1928 	size_t	len;
1929 
1930 	/*
1931 	 * For TCP_CCALGOOPT forward the control to CC module, for both
1932 	 * SOPT_SET and SOPT_GET.
1933 	 */
1934 	switch (sopt->sopt_name) {
1935 	case TCP_CCALGOOPT:
1936 		INP_WUNLOCK(inp);
1937 		if (sopt->sopt_valsize > CC_ALGOOPT_LIMIT)
1938 			return (EINVAL);
1939 		pbuf = malloc(sopt->sopt_valsize, M_TEMP, M_WAITOK | M_ZERO);
1940 		error = sooptcopyin(sopt, pbuf, sopt->sopt_valsize,
1941 		    sopt->sopt_valsize);
1942 		if (error) {
1943 			free(pbuf, M_TEMP);
1944 			return (error);
1945 		}
1946 		INP_WLOCK_RECHECK_CLEANUP(inp, free(pbuf, M_TEMP));
1947 		if (CC_ALGO(tp)->ctl_output != NULL)
1948 			error = CC_ALGO(tp)->ctl_output(tp->ccv, sopt, pbuf);
1949 		else
1950 			error = ENOENT;
1951 		INP_WUNLOCK(inp);
1952 		if (error == 0 && sopt->sopt_dir == SOPT_GET)
1953 			error = sooptcopyout(sopt, pbuf, sopt->sopt_valsize);
1954 		free(pbuf, M_TEMP);
1955 		return (error);
1956 	}
1957 
1958 	switch (sopt->sopt_dir) {
1959 	case SOPT_SET:
1960 		switch (sopt->sopt_name) {
1961 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
1962 		case TCP_MD5SIG:
1963 			if (!TCPMD5_ENABLED()) {
1964 				INP_WUNLOCK(inp);
1965 				return (ENOPROTOOPT);
1966 			}
1967 			error = TCPMD5_PCBCTL(inp, sopt);
1968 			if (error)
1969 				return (error);
1970 			goto unlock_and_done;
1971 #endif /* IPSEC */
1972 
1973 		case TCP_NODELAY:
1974 		case TCP_NOOPT:
1975 		case TCP_LRD:
1976 			INP_WUNLOCK(inp);
1977 			error = sooptcopyin(sopt, &optval, sizeof optval,
1978 			    sizeof optval);
1979 			if (error)
1980 				return (error);
1981 
1982 			INP_WLOCK_RECHECK(inp);
1983 			switch (sopt->sopt_name) {
1984 			case TCP_NODELAY:
1985 				opt = TF_NODELAY;
1986 				break;
1987 			case TCP_NOOPT:
1988 				opt = TF_NOOPT;
1989 				break;
1990 			case TCP_LRD:
1991 				opt = TF_LRD;
1992 				break;
1993 			default:
1994 				opt = 0; /* dead code to fool gcc */
1995 				break;
1996 			}
1997 
1998 			if (optval)
1999 				tp->t_flags |= opt;
2000 			else
2001 				tp->t_flags &= ~opt;
2002 unlock_and_done:
2003 #ifdef TCP_OFFLOAD
2004 			if (tp->t_flags & TF_TOE) {
2005 				tcp_offload_ctloutput(tp, sopt->sopt_dir,
2006 				    sopt->sopt_name);
2007 			}
2008 #endif
2009 			INP_WUNLOCK(inp);
2010 			break;
2011 
2012 		case TCP_NOPUSH:
2013 			INP_WUNLOCK(inp);
2014 			error = sooptcopyin(sopt, &optval, sizeof optval,
2015 			    sizeof optval);
2016 			if (error)
2017 				return (error);
2018 
2019 			INP_WLOCK_RECHECK(inp);
2020 			if (optval)
2021 				tp->t_flags |= TF_NOPUSH;
2022 			else if (tp->t_flags & TF_NOPUSH) {
2023 				tp->t_flags &= ~TF_NOPUSH;
2024 				if (TCPS_HAVEESTABLISHED(tp->t_state)) {
2025 					struct epoch_tracker et;
2026 
2027 					NET_EPOCH_ENTER(et);
2028 					error = tp->t_fb->tfb_tcp_output(tp);
2029 					NET_EPOCH_EXIT(et);
2030 				}
2031 			}
2032 			goto unlock_and_done;
2033 
2034 		case TCP_REMOTE_UDP_ENCAPS_PORT:
2035 			INP_WUNLOCK(inp);
2036 			error = sooptcopyin(sopt, &optval, sizeof optval,
2037 			    sizeof optval);
2038 			if (error)
2039 				return (error);
2040 			if ((optval < TCP_TUNNELING_PORT_MIN) ||
2041 			    (optval > TCP_TUNNELING_PORT_MAX)) {
2042 				/* Its got to be in range */
2043 				return (EINVAL);
2044 			}
2045 			if ((V_tcp_udp_tunneling_port == 0) && (optval != 0)) {
2046 				/* You have to have enabled a UDP tunneling port first */
2047 				return (EINVAL);
2048 			}
2049 			INP_WLOCK_RECHECK(inp);
2050 			if (tp->t_state != TCPS_CLOSED) {
2051 				/* You can't change after you are connected */
2052 				error = EINVAL;
2053 			} else {
2054 				/* Ok we are all good set the port */
2055 				tp->t_port = htons(optval);
2056 			}
2057 			goto unlock_and_done;
2058 
2059 		case TCP_MAXSEG:
2060 			INP_WUNLOCK(inp);
2061 			error = sooptcopyin(sopt, &optval, sizeof optval,
2062 			    sizeof optval);
2063 			if (error)
2064 				return (error);
2065 
2066 			INP_WLOCK_RECHECK(inp);
2067 			if (optval > 0 && optval <= tp->t_maxseg &&
2068 			    optval + 40 >= V_tcp_minmss)
2069 				tp->t_maxseg = optval;
2070 			else
2071 				error = EINVAL;
2072 			goto unlock_and_done;
2073 
2074 		case TCP_INFO:
2075 			INP_WUNLOCK(inp);
2076 			error = EINVAL;
2077 			break;
2078 
2079 		case TCP_STATS:
2080 			INP_WUNLOCK(inp);
2081 #ifdef STATS
2082 			error = sooptcopyin(sopt, &optval, sizeof optval,
2083 			    sizeof optval);
2084 			if (error)
2085 				return (error);
2086 
2087 			if (optval > 0)
2088 				sbp = stats_blob_alloc(
2089 				    V_tcp_perconn_stats_dflt_tpl, 0);
2090 			else
2091 				sbp = NULL;
2092 
2093 			INP_WLOCK_RECHECK(inp);
2094 			if ((tp->t_stats != NULL && sbp == NULL) ||
2095 			    (tp->t_stats == NULL && sbp != NULL)) {
2096 				struct statsblob *t = tp->t_stats;
2097 				tp->t_stats = sbp;
2098 				sbp = t;
2099 			}
2100 			INP_WUNLOCK(inp);
2101 
2102 			stats_blob_destroy(sbp);
2103 #else
2104 			return (EOPNOTSUPP);
2105 #endif /* !STATS */
2106 			break;
2107 
2108 		case TCP_CONGESTION:
2109 			INP_WUNLOCK(inp);
2110 			error = sooptcopyin(sopt, buf, TCP_CA_NAME_MAX - 1, 1);
2111 			if (error)
2112 				break;
2113 			buf[sopt->sopt_valsize] = '\0';
2114 			INP_WLOCK_RECHECK(inp);
2115 			CC_LIST_RLOCK();
2116 			STAILQ_FOREACH(algo, &cc_list, entries)
2117 				if (strncmp(buf, algo->name,
2118 				    TCP_CA_NAME_MAX) == 0)
2119 					break;
2120 			CC_LIST_RUNLOCK();
2121 			if (algo == NULL) {
2122 				INP_WUNLOCK(inp);
2123 				error = EINVAL;
2124 				break;
2125 			}
2126 			/*
2127 			 * We hold a write lock over the tcb so it's safe to
2128 			 * do these things without ordering concerns.
2129 			 */
2130 			if (CC_ALGO(tp)->cb_destroy != NULL)
2131 				CC_ALGO(tp)->cb_destroy(tp->ccv);
2132 			CC_DATA(tp) = NULL;
2133 			CC_ALGO(tp) = algo;
2134 			/*
2135 			 * If something goes pear shaped initialising the new
2136 			 * algo, fall back to newreno (which does not
2137 			 * require initialisation).
2138 			 */
2139 			if (algo->cb_init != NULL &&
2140 			    algo->cb_init(tp->ccv) != 0) {
2141 				CC_ALGO(tp) = &newreno_cc_algo;
2142 				/*
2143 				 * The only reason init should fail is
2144 				 * because of malloc.
2145 				 */
2146 				error = ENOMEM;
2147 			}
2148 			INP_WUNLOCK(inp);
2149 			break;
2150 
2151 		case TCP_REUSPORT_LB_NUMA:
2152 			INP_WUNLOCK(inp);
2153 			error = sooptcopyin(sopt, &optval, sizeof(optval),
2154 			    sizeof(optval));
2155 			INP_WLOCK_RECHECK(inp);
2156 			if (!error)
2157 				error = in_pcblbgroup_numa(inp, optval);
2158 			INP_WUNLOCK(inp);
2159 			break;
2160 
2161 #ifdef KERN_TLS
2162 		case TCP_TXTLS_ENABLE:
2163 			INP_WUNLOCK(inp);
2164 			error = copyin_tls_enable(sopt, &tls);
2165 			if (error)
2166 				break;
2167 			error = ktls_enable_tx(so, &tls);
2168 			break;
2169 		case TCP_TXTLS_MODE:
2170 			INP_WUNLOCK(inp);
2171 			error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui));
2172 			if (error)
2173 				return (error);
2174 
2175 			INP_WLOCK_RECHECK(inp);
2176 			error = ktls_set_tx_mode(so, ui);
2177 			INP_WUNLOCK(inp);
2178 			break;
2179 		case TCP_RXTLS_ENABLE:
2180 			INP_WUNLOCK(inp);
2181 			error = sooptcopyin(sopt, &tls, sizeof(tls),
2182 			    sizeof(tls));
2183 			if (error)
2184 				break;
2185 			error = ktls_enable_rx(so, &tls);
2186 			break;
2187 #endif
2188 
2189 		case TCP_KEEPIDLE:
2190 		case TCP_KEEPINTVL:
2191 		case TCP_KEEPINIT:
2192 			INP_WUNLOCK(inp);
2193 			error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui));
2194 			if (error)
2195 				return (error);
2196 
2197 			if (ui > (UINT_MAX / hz)) {
2198 				error = EINVAL;
2199 				break;
2200 			}
2201 			ui *= hz;
2202 
2203 			INP_WLOCK_RECHECK(inp);
2204 			switch (sopt->sopt_name) {
2205 			case TCP_KEEPIDLE:
2206 				tp->t_keepidle = ui;
2207 				/*
2208 				 * XXX: better check current remaining
2209 				 * timeout and "merge" it with new value.
2210 				 */
2211 				if ((tp->t_state > TCPS_LISTEN) &&
2212 				    (tp->t_state <= TCPS_CLOSING))
2213 					tcp_timer_activate(tp, TT_KEEP,
2214 					    TP_KEEPIDLE(tp));
2215 				break;
2216 			case TCP_KEEPINTVL:
2217 				tp->t_keepintvl = ui;
2218 				if ((tp->t_state == TCPS_FIN_WAIT_2) &&
2219 				    (TP_MAXIDLE(tp) > 0))
2220 					tcp_timer_activate(tp, TT_2MSL,
2221 					    TP_MAXIDLE(tp));
2222 				break;
2223 			case TCP_KEEPINIT:
2224 				tp->t_keepinit = ui;
2225 				if (tp->t_state == TCPS_SYN_RECEIVED ||
2226 				    tp->t_state == TCPS_SYN_SENT)
2227 					tcp_timer_activate(tp, TT_KEEP,
2228 					    TP_KEEPINIT(tp));
2229 				break;
2230 			}
2231 			goto unlock_and_done;
2232 
2233 		case TCP_KEEPCNT:
2234 			INP_WUNLOCK(inp);
2235 			error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui));
2236 			if (error)
2237 				return (error);
2238 
2239 			INP_WLOCK_RECHECK(inp);
2240 			tp->t_keepcnt = ui;
2241 			if ((tp->t_state == TCPS_FIN_WAIT_2) &&
2242 			    (TP_MAXIDLE(tp) > 0))
2243 				tcp_timer_activate(tp, TT_2MSL,
2244 				    TP_MAXIDLE(tp));
2245 			goto unlock_and_done;
2246 
2247 #ifdef TCPPCAP
2248 		case TCP_PCAP_OUT:
2249 		case TCP_PCAP_IN:
2250 			INP_WUNLOCK(inp);
2251 			error = sooptcopyin(sopt, &optval, sizeof optval,
2252 			    sizeof optval);
2253 			if (error)
2254 				return (error);
2255 
2256 			INP_WLOCK_RECHECK(inp);
2257 			if (optval >= 0)
2258 				tcp_pcap_set_sock_max(TCP_PCAP_OUT ?
2259 					&(tp->t_outpkts) : &(tp->t_inpkts),
2260 					optval);
2261 			else
2262 				error = EINVAL;
2263 			goto unlock_and_done;
2264 #endif
2265 
2266 		case TCP_FASTOPEN: {
2267 			struct tcp_fastopen tfo_optval;
2268 
2269 			INP_WUNLOCK(inp);
2270 			if (!V_tcp_fastopen_client_enable &&
2271 			    !V_tcp_fastopen_server_enable)
2272 				return (EPERM);
2273 
2274 			error = sooptcopyin(sopt, &tfo_optval,
2275 				    sizeof(tfo_optval), sizeof(int));
2276 			if (error)
2277 				return (error);
2278 
2279 			INP_WLOCK_RECHECK(inp);
2280 			if ((tp->t_state != TCPS_CLOSED) &&
2281 			    (tp->t_state != TCPS_LISTEN)) {
2282 				error = EINVAL;
2283 				goto unlock_and_done;
2284 			}
2285 			if (tfo_optval.enable) {
2286 				if (tp->t_state == TCPS_LISTEN) {
2287 					if (!V_tcp_fastopen_server_enable) {
2288 						error = EPERM;
2289 						goto unlock_and_done;
2290 					}
2291 
2292 					if (tp->t_tfo_pending == NULL)
2293 						tp->t_tfo_pending =
2294 						    tcp_fastopen_alloc_counter();
2295 				} else {
2296 					/*
2297 					 * If a pre-shared key was provided,
2298 					 * stash it in the client cookie
2299 					 * field of the tcpcb for use during
2300 					 * connect.
2301 					 */
2302 					if (sopt->sopt_valsize ==
2303 					    sizeof(tfo_optval)) {
2304 						memcpy(tp->t_tfo_cookie.client,
2305 						       tfo_optval.psk,
2306 						       TCP_FASTOPEN_PSK_LEN);
2307 						tp->t_tfo_client_cookie_len =
2308 						    TCP_FASTOPEN_PSK_LEN;
2309 					}
2310 				}
2311 				tp->t_flags |= TF_FASTOPEN;
2312 			} else
2313 				tp->t_flags &= ~TF_FASTOPEN;
2314 			goto unlock_and_done;
2315 		}
2316 
2317 #ifdef TCP_BLACKBOX
2318 		case TCP_LOG:
2319 			INP_WUNLOCK(inp);
2320 			error = sooptcopyin(sopt, &optval, sizeof optval,
2321 			    sizeof optval);
2322 			if (error)
2323 				return (error);
2324 
2325 			INP_WLOCK_RECHECK(inp);
2326 			error = tcp_log_state_change(tp, optval);
2327 			goto unlock_and_done;
2328 
2329 		case TCP_LOGBUF:
2330 			INP_WUNLOCK(inp);
2331 			error = EINVAL;
2332 			break;
2333 
2334 		case TCP_LOGID:
2335 			INP_WUNLOCK(inp);
2336 			error = sooptcopyin(sopt, buf, TCP_LOG_ID_LEN - 1, 0);
2337 			if (error)
2338 				break;
2339 			buf[sopt->sopt_valsize] = '\0';
2340 			INP_WLOCK_RECHECK(inp);
2341 			error = tcp_log_set_id(tp, buf);
2342 			/* tcp_log_set_id() unlocks the INP. */
2343 			break;
2344 
2345 		case TCP_LOGDUMP:
2346 		case TCP_LOGDUMPID:
2347 			INP_WUNLOCK(inp);
2348 			error =
2349 			    sooptcopyin(sopt, buf, TCP_LOG_REASON_LEN - 1, 0);
2350 			if (error)
2351 				break;
2352 			buf[sopt->sopt_valsize] = '\0';
2353 			INP_WLOCK_RECHECK(inp);
2354 			if (sopt->sopt_name == TCP_LOGDUMP) {
2355 				error = tcp_log_dump_tp_logbuf(tp, buf,
2356 				    M_WAITOK, true);
2357 				INP_WUNLOCK(inp);
2358 			} else {
2359 				tcp_log_dump_tp_bucket_logbufs(tp, buf);
2360 				/*
2361 				 * tcp_log_dump_tp_bucket_logbufs() drops the
2362 				 * INP lock.
2363 				 */
2364 			}
2365 			break;
2366 #endif
2367 
2368 		default:
2369 			INP_WUNLOCK(inp);
2370 			error = ENOPROTOOPT;
2371 			break;
2372 		}
2373 		break;
2374 
2375 	case SOPT_GET:
2376 		tp = intotcpcb(inp);
2377 		switch (sopt->sopt_name) {
2378 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
2379 		case TCP_MD5SIG:
2380 			if (!TCPMD5_ENABLED()) {
2381 				INP_WUNLOCK(inp);
2382 				return (ENOPROTOOPT);
2383 			}
2384 			error = TCPMD5_PCBCTL(inp, sopt);
2385 			break;
2386 #endif
2387 
2388 		case TCP_NODELAY:
2389 			optval = tp->t_flags & TF_NODELAY;
2390 			INP_WUNLOCK(inp);
2391 			error = sooptcopyout(sopt, &optval, sizeof optval);
2392 			break;
2393 		case TCP_MAXSEG:
2394 			optval = tp->t_maxseg;
2395 			INP_WUNLOCK(inp);
2396 			error = sooptcopyout(sopt, &optval, sizeof optval);
2397 			break;
2398 		case TCP_REMOTE_UDP_ENCAPS_PORT:
2399 			optval = ntohs(tp->t_port);
2400 			INP_WUNLOCK(inp);
2401 			error = sooptcopyout(sopt, &optval, sizeof optval);
2402 			break;
2403 		case TCP_NOOPT:
2404 			optval = tp->t_flags & TF_NOOPT;
2405 			INP_WUNLOCK(inp);
2406 			error = sooptcopyout(sopt, &optval, sizeof optval);
2407 			break;
2408 		case TCP_NOPUSH:
2409 			optval = tp->t_flags & TF_NOPUSH;
2410 			INP_WUNLOCK(inp);
2411 			error = sooptcopyout(sopt, &optval, sizeof optval);
2412 			break;
2413 		case TCP_INFO:
2414 			tcp_fill_info(tp, &ti);
2415 			INP_WUNLOCK(inp);
2416 			error = sooptcopyout(sopt, &ti, sizeof ti);
2417 			break;
2418 		case TCP_STATS:
2419 			{
2420 #ifdef STATS
2421 			int nheld;
2422 			TYPEOF_MEMBER(struct statsblob, flags) sbflags = 0;
2423 
2424 			error = 0;
2425 			socklen_t outsbsz = sopt->sopt_valsize;
2426 			if (tp->t_stats == NULL)
2427 				error = ENOENT;
2428 			else if (outsbsz >= tp->t_stats->cursz)
2429 				outsbsz = tp->t_stats->cursz;
2430 			else if (outsbsz >= sizeof(struct statsblob))
2431 				outsbsz = sizeof(struct statsblob);
2432 			else
2433 				error = EINVAL;
2434 			INP_WUNLOCK(inp);
2435 			if (error)
2436 				break;
2437 
2438 			sbp = sopt->sopt_val;
2439 			nheld = atop(round_page(((vm_offset_t)sbp) +
2440 			    (vm_size_t)outsbsz) - trunc_page((vm_offset_t)sbp));
2441 			vm_page_t ma[nheld];
2442 			if (vm_fault_quick_hold_pages(
2443 			    &curproc->p_vmspace->vm_map, (vm_offset_t)sbp,
2444 			    outsbsz, VM_PROT_READ | VM_PROT_WRITE, ma,
2445 			    nheld) < 0) {
2446 				error = EFAULT;
2447 				break;
2448 			}
2449 
2450 			if ((error = copyin_nofault(&(sbp->flags), &sbflags,
2451 			    SIZEOF_MEMBER(struct statsblob, flags))))
2452 				goto unhold;
2453 
2454 			INP_WLOCK_RECHECK(inp);
2455 			error = stats_blob_snapshot(&sbp, outsbsz, tp->t_stats,
2456 			    sbflags | SB_CLONE_USRDSTNOFAULT);
2457 			INP_WUNLOCK(inp);
2458 			sopt->sopt_valsize = outsbsz;
2459 unhold:
2460 			vm_page_unhold_pages(ma, nheld);
2461 #else
2462 			INP_WUNLOCK(inp);
2463 			error = EOPNOTSUPP;
2464 #endif /* !STATS */
2465 			break;
2466 			}
2467 		case TCP_CONGESTION:
2468 			len = strlcpy(buf, CC_ALGO(tp)->name, TCP_CA_NAME_MAX);
2469 			INP_WUNLOCK(inp);
2470 			error = sooptcopyout(sopt, buf, len + 1);
2471 			break;
2472 		case TCP_KEEPIDLE:
2473 		case TCP_KEEPINTVL:
2474 		case TCP_KEEPINIT:
2475 		case TCP_KEEPCNT:
2476 			switch (sopt->sopt_name) {
2477 			case TCP_KEEPIDLE:
2478 				ui = TP_KEEPIDLE(tp) / hz;
2479 				break;
2480 			case TCP_KEEPINTVL:
2481 				ui = TP_KEEPINTVL(tp) / hz;
2482 				break;
2483 			case TCP_KEEPINIT:
2484 				ui = TP_KEEPINIT(tp) / hz;
2485 				break;
2486 			case TCP_KEEPCNT:
2487 				ui = TP_KEEPCNT(tp);
2488 				break;
2489 			}
2490 			INP_WUNLOCK(inp);
2491 			error = sooptcopyout(sopt, &ui, sizeof(ui));
2492 			break;
2493 #ifdef TCPPCAP
2494 		case TCP_PCAP_OUT:
2495 		case TCP_PCAP_IN:
2496 			optval = tcp_pcap_get_sock_max(TCP_PCAP_OUT ?
2497 					&(tp->t_outpkts) : &(tp->t_inpkts));
2498 			INP_WUNLOCK(inp);
2499 			error = sooptcopyout(sopt, &optval, sizeof optval);
2500 			break;
2501 #endif
2502 		case TCP_FASTOPEN:
2503 			optval = tp->t_flags & TF_FASTOPEN;
2504 			INP_WUNLOCK(inp);
2505 			error = sooptcopyout(sopt, &optval, sizeof optval);
2506 			break;
2507 #ifdef TCP_BLACKBOX
2508 		case TCP_LOG:
2509 			optval = tp->t_logstate;
2510 			INP_WUNLOCK(inp);
2511 			error = sooptcopyout(sopt, &optval, sizeof(optval));
2512 			break;
2513 		case TCP_LOGBUF:
2514 			/* tcp_log_getlogbuf() does INP_WUNLOCK(inp) */
2515 			error = tcp_log_getlogbuf(sopt, tp);
2516 			break;
2517 		case TCP_LOGID:
2518 			len = tcp_log_get_id(tp, buf);
2519 			INP_WUNLOCK(inp);
2520 			error = sooptcopyout(sopt, buf, len + 1);
2521 			break;
2522 		case TCP_LOGDUMP:
2523 		case TCP_LOGDUMPID:
2524 			INP_WUNLOCK(inp);
2525 			error = EINVAL;
2526 			break;
2527 #endif
2528 #ifdef KERN_TLS
2529 		case TCP_TXTLS_MODE:
2530 			optval = ktls_get_tx_mode(so);
2531 			INP_WUNLOCK(inp);
2532 			error = sooptcopyout(sopt, &optval, sizeof(optval));
2533 			break;
2534 		case TCP_RXTLS_MODE:
2535 			optval = ktls_get_rx_mode(so);
2536 			INP_WUNLOCK(inp);
2537 			error = sooptcopyout(sopt, &optval, sizeof(optval));
2538 			break;
2539 #endif
2540 		case TCP_LRD:
2541 			optval = tp->t_flags & TF_LRD;
2542 			INP_WUNLOCK(inp);
2543 			error = sooptcopyout(sopt, &optval, sizeof optval);
2544 			break;
2545 		default:
2546 			INP_WUNLOCK(inp);
2547 			error = ENOPROTOOPT;
2548 			break;
2549 		}
2550 		break;
2551 	}
2552 	return (error);
2553 }
2554 #undef INP_WLOCK_RECHECK
2555 #undef INP_WLOCK_RECHECK_CLEANUP
2556 
2557 /*
2558  * Initiate (or continue) disconnect.
2559  * If embryonic state, just send reset (once).
2560  * If in ``let data drain'' option and linger null, just drop.
2561  * Otherwise (hard), mark socket disconnecting and drop
2562  * current input data; switch states based on user close, and
2563  * send segment to peer (with FIN).
2564  */
2565 static void
2566 tcp_disconnect(struct tcpcb *tp)
2567 {
2568 	struct inpcb *inp = tp->t_inpcb;
2569 	struct socket *so = inp->inp_socket;
2570 
2571 	NET_EPOCH_ASSERT();
2572 	INP_WLOCK_ASSERT(inp);
2573 
2574 	/*
2575 	 * Neither tcp_close() nor tcp_drop() should return NULL, as the
2576 	 * socket is still open.
2577 	 */
2578 	if (tp->t_state < TCPS_ESTABLISHED &&
2579 	    !(tp->t_state > TCPS_LISTEN && IS_FASTOPEN(tp->t_flags))) {
2580 		tp = tcp_close(tp);
2581 		KASSERT(tp != NULL,
2582 		    ("tcp_disconnect: tcp_close() returned NULL"));
2583 	} else if ((so->so_options & SO_LINGER) && so->so_linger == 0) {
2584 		tp = tcp_drop(tp, 0);
2585 		KASSERT(tp != NULL,
2586 		    ("tcp_disconnect: tcp_drop() returned NULL"));
2587 	} else {
2588 		soisdisconnecting(so);
2589 		sbflush(&so->so_rcv);
2590 		tcp_usrclosed(tp);
2591 		if (!(inp->inp_flags & INP_DROPPED))
2592 			tp->t_fb->tfb_tcp_output(tp);
2593 	}
2594 }
2595 
2596 /*
2597  * User issued close, and wish to trail through shutdown states:
2598  * if never received SYN, just forget it.  If got a SYN from peer,
2599  * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
2600  * If already got a FIN from peer, then almost done; go to LAST_ACK
2601  * state.  In all other cases, have already sent FIN to peer (e.g.
2602  * after PRU_SHUTDOWN), and just have to play tedious game waiting
2603  * for peer to send FIN or not respond to keep-alives, etc.
2604  * We can let the user exit from the close as soon as the FIN is acked.
2605  */
2606 static void
2607 tcp_usrclosed(struct tcpcb *tp)
2608 {
2609 
2610 	NET_EPOCH_ASSERT();
2611 	INP_WLOCK_ASSERT(tp->t_inpcb);
2612 
2613 	switch (tp->t_state) {
2614 	case TCPS_LISTEN:
2615 #ifdef TCP_OFFLOAD
2616 		tcp_offload_listen_stop(tp);
2617 #endif
2618 		tcp_state_change(tp, TCPS_CLOSED);
2619 		/* FALLTHROUGH */
2620 	case TCPS_CLOSED:
2621 		tp = tcp_close(tp);
2622 		/*
2623 		 * tcp_close() should never return NULL here as the socket is
2624 		 * still open.
2625 		 */
2626 		KASSERT(tp != NULL,
2627 		    ("tcp_usrclosed: tcp_close() returned NULL"));
2628 		break;
2629 
2630 	case TCPS_SYN_SENT:
2631 	case TCPS_SYN_RECEIVED:
2632 		tp->t_flags |= TF_NEEDFIN;
2633 		break;
2634 
2635 	case TCPS_ESTABLISHED:
2636 		tcp_state_change(tp, TCPS_FIN_WAIT_1);
2637 		break;
2638 
2639 	case TCPS_CLOSE_WAIT:
2640 		tcp_state_change(tp, TCPS_LAST_ACK);
2641 		break;
2642 	}
2643 	if ((tp->t_state == TCPS_LAST_ACK) &&
2644 	    (tp->t_flags & TF_SENTFIN)) {
2645 		/*
2646 		 * If we have reached LAST_ACK, and
2647 		 * we sent a FIN (e.g. via MSG_EOR), then
2648 		 * we really should move to either FIN_WAIT_1
2649 		 * or FIN_WAIT_2 depending on snd_max/snd_una.
2650 		 */
2651 		if (tp->snd_una == tp->snd_max) {
2652 			/* The FIN is acked */
2653 			tcp_state_change(tp, TCPS_FIN_WAIT_2);
2654 		} else {
2655 			/* The FIN is still outstanding */
2656 			tcp_state_change(tp, TCPS_FIN_WAIT_1);
2657 		}
2658 	}
2659 	if (tp->t_state >= TCPS_FIN_WAIT_2) {
2660 		soisdisconnected(tp->t_inpcb->inp_socket);
2661 		/* Prevent the connection hanging in FIN_WAIT_2 forever. */
2662 		if (tp->t_state == TCPS_FIN_WAIT_2) {
2663 			int timeout;
2664 
2665 			timeout = (tcp_fast_finwait2_recycle) ?
2666 			    tcp_finwait2_timeout : TP_MAXIDLE(tp);
2667 			tcp_timer_activate(tp, TT_2MSL, timeout);
2668 		}
2669 	}
2670 }
2671 
2672 #ifdef DDB
2673 static void
2674 db_print_indent(int indent)
2675 {
2676 	int i;
2677 
2678 	for (i = 0; i < indent; i++)
2679 		db_printf(" ");
2680 }
2681 
2682 static void
2683 db_print_tstate(int t_state)
2684 {
2685 
2686 	switch (t_state) {
2687 	case TCPS_CLOSED:
2688 		db_printf("TCPS_CLOSED");
2689 		return;
2690 
2691 	case TCPS_LISTEN:
2692 		db_printf("TCPS_LISTEN");
2693 		return;
2694 
2695 	case TCPS_SYN_SENT:
2696 		db_printf("TCPS_SYN_SENT");
2697 		return;
2698 
2699 	case TCPS_SYN_RECEIVED:
2700 		db_printf("TCPS_SYN_RECEIVED");
2701 		return;
2702 
2703 	case TCPS_ESTABLISHED:
2704 		db_printf("TCPS_ESTABLISHED");
2705 		return;
2706 
2707 	case TCPS_CLOSE_WAIT:
2708 		db_printf("TCPS_CLOSE_WAIT");
2709 		return;
2710 
2711 	case TCPS_FIN_WAIT_1:
2712 		db_printf("TCPS_FIN_WAIT_1");
2713 		return;
2714 
2715 	case TCPS_CLOSING:
2716 		db_printf("TCPS_CLOSING");
2717 		return;
2718 
2719 	case TCPS_LAST_ACK:
2720 		db_printf("TCPS_LAST_ACK");
2721 		return;
2722 
2723 	case TCPS_FIN_WAIT_2:
2724 		db_printf("TCPS_FIN_WAIT_2");
2725 		return;
2726 
2727 	case TCPS_TIME_WAIT:
2728 		db_printf("TCPS_TIME_WAIT");
2729 		return;
2730 
2731 	default:
2732 		db_printf("unknown");
2733 		return;
2734 	}
2735 }
2736 
2737 static void
2738 db_print_tflags(u_int t_flags)
2739 {
2740 	int comma;
2741 
2742 	comma = 0;
2743 	if (t_flags & TF_ACKNOW) {
2744 		db_printf("%sTF_ACKNOW", comma ? ", " : "");
2745 		comma = 1;
2746 	}
2747 	if (t_flags & TF_DELACK) {
2748 		db_printf("%sTF_DELACK", comma ? ", " : "");
2749 		comma = 1;
2750 	}
2751 	if (t_flags & TF_NODELAY) {
2752 		db_printf("%sTF_NODELAY", comma ? ", " : "");
2753 		comma = 1;
2754 	}
2755 	if (t_flags & TF_NOOPT) {
2756 		db_printf("%sTF_NOOPT", comma ? ", " : "");
2757 		comma = 1;
2758 	}
2759 	if (t_flags & TF_SENTFIN) {
2760 		db_printf("%sTF_SENTFIN", comma ? ", " : "");
2761 		comma = 1;
2762 	}
2763 	if (t_flags & TF_REQ_SCALE) {
2764 		db_printf("%sTF_REQ_SCALE", comma ? ", " : "");
2765 		comma = 1;
2766 	}
2767 	if (t_flags & TF_RCVD_SCALE) {
2768 		db_printf("%sTF_RECVD_SCALE", comma ? ", " : "");
2769 		comma = 1;
2770 	}
2771 	if (t_flags & TF_REQ_TSTMP) {
2772 		db_printf("%sTF_REQ_TSTMP", comma ? ", " : "");
2773 		comma = 1;
2774 	}
2775 	if (t_flags & TF_RCVD_TSTMP) {
2776 		db_printf("%sTF_RCVD_TSTMP", comma ? ", " : "");
2777 		comma = 1;
2778 	}
2779 	if (t_flags & TF_SACK_PERMIT) {
2780 		db_printf("%sTF_SACK_PERMIT", comma ? ", " : "");
2781 		comma = 1;
2782 	}
2783 	if (t_flags & TF_NEEDSYN) {
2784 		db_printf("%sTF_NEEDSYN", comma ? ", " : "");
2785 		comma = 1;
2786 	}
2787 	if (t_flags & TF_NEEDFIN) {
2788 		db_printf("%sTF_NEEDFIN", comma ? ", " : "");
2789 		comma = 1;
2790 	}
2791 	if (t_flags & TF_NOPUSH) {
2792 		db_printf("%sTF_NOPUSH", comma ? ", " : "");
2793 		comma = 1;
2794 	}
2795 	if (t_flags & TF_MORETOCOME) {
2796 		db_printf("%sTF_MORETOCOME", comma ? ", " : "");
2797 		comma = 1;
2798 	}
2799 	if (t_flags & TF_LQ_OVERFLOW) {
2800 		db_printf("%sTF_LQ_OVERFLOW", comma ? ", " : "");
2801 		comma = 1;
2802 	}
2803 	if (t_flags & TF_LASTIDLE) {
2804 		db_printf("%sTF_LASTIDLE", comma ? ", " : "");
2805 		comma = 1;
2806 	}
2807 	if (t_flags & TF_RXWIN0SENT) {
2808 		db_printf("%sTF_RXWIN0SENT", comma ? ", " : "");
2809 		comma = 1;
2810 	}
2811 	if (t_flags & TF_FASTRECOVERY) {
2812 		db_printf("%sTF_FASTRECOVERY", comma ? ", " : "");
2813 		comma = 1;
2814 	}
2815 	if (t_flags & TF_CONGRECOVERY) {
2816 		db_printf("%sTF_CONGRECOVERY", comma ? ", " : "");
2817 		comma = 1;
2818 	}
2819 	if (t_flags & TF_WASFRECOVERY) {
2820 		db_printf("%sTF_WASFRECOVERY", comma ? ", " : "");
2821 		comma = 1;
2822 	}
2823 	if (t_flags & TF_SIGNATURE) {
2824 		db_printf("%sTF_SIGNATURE", comma ? ", " : "");
2825 		comma = 1;
2826 	}
2827 	if (t_flags & TF_FORCEDATA) {
2828 		db_printf("%sTF_FORCEDATA", comma ? ", " : "");
2829 		comma = 1;
2830 	}
2831 	if (t_flags & TF_TSO) {
2832 		db_printf("%sTF_TSO", comma ? ", " : "");
2833 		comma = 1;
2834 	}
2835 	if (t_flags & TF_FASTOPEN) {
2836 		db_printf("%sTF_FASTOPEN", comma ? ", " : "");
2837 		comma = 1;
2838 	}
2839 }
2840 
2841 static void
2842 db_print_tflags2(u_int t_flags2)
2843 {
2844 	int comma;
2845 
2846 	comma = 0;
2847 	if (t_flags2 & TF2_ECN_PERMIT) {
2848 		db_printf("%sTF2_ECN_PERMIT", comma ? ", " : "");
2849 		comma = 1;
2850 	}
2851 }
2852 
2853 static void
2854 db_print_toobflags(char t_oobflags)
2855 {
2856 	int comma;
2857 
2858 	comma = 0;
2859 	if (t_oobflags & TCPOOB_HAVEDATA) {
2860 		db_printf("%sTCPOOB_HAVEDATA", comma ? ", " : "");
2861 		comma = 1;
2862 	}
2863 	if (t_oobflags & TCPOOB_HADDATA) {
2864 		db_printf("%sTCPOOB_HADDATA", comma ? ", " : "");
2865 		comma = 1;
2866 	}
2867 }
2868 
2869 static void
2870 db_print_tcpcb(struct tcpcb *tp, const char *name, int indent)
2871 {
2872 
2873 	db_print_indent(indent);
2874 	db_printf("%s at %p\n", name, tp);
2875 
2876 	indent += 2;
2877 
2878 	db_print_indent(indent);
2879 	db_printf("t_segq first: %p   t_segqlen: %d   t_dupacks: %d\n",
2880 	   TAILQ_FIRST(&tp->t_segq), tp->t_segqlen, tp->t_dupacks);
2881 
2882 	db_print_indent(indent);
2883 	db_printf("tt_rexmt: %p   tt_persist: %p   tt_keep: %p\n",
2884 	    &tp->t_timers->tt_rexmt, &tp->t_timers->tt_persist, &tp->t_timers->tt_keep);
2885 
2886 	db_print_indent(indent);
2887 	db_printf("tt_2msl: %p   tt_delack: %p   t_inpcb: %p\n", &tp->t_timers->tt_2msl,
2888 	    &tp->t_timers->tt_delack, tp->t_inpcb);
2889 
2890 	db_print_indent(indent);
2891 	db_printf("t_state: %d (", tp->t_state);
2892 	db_print_tstate(tp->t_state);
2893 	db_printf(")\n");
2894 
2895 	db_print_indent(indent);
2896 	db_printf("t_flags: 0x%x (", tp->t_flags);
2897 	db_print_tflags(tp->t_flags);
2898 	db_printf(")\n");
2899 
2900 	db_print_indent(indent);
2901 	db_printf("t_flags2: 0x%x (", tp->t_flags2);
2902 	db_print_tflags2(tp->t_flags2);
2903 	db_printf(")\n");
2904 
2905 	db_print_indent(indent);
2906 	db_printf("snd_una: 0x%08x   snd_max: 0x%08x   snd_nxt: x0%08x\n",
2907 	    tp->snd_una, tp->snd_max, tp->snd_nxt);
2908 
2909 	db_print_indent(indent);
2910 	db_printf("snd_up: 0x%08x   snd_wl1: 0x%08x   snd_wl2: 0x%08x\n",
2911 	   tp->snd_up, tp->snd_wl1, tp->snd_wl2);
2912 
2913 	db_print_indent(indent);
2914 	db_printf("iss: 0x%08x   irs: 0x%08x   rcv_nxt: 0x%08x\n",
2915 	    tp->iss, tp->irs, tp->rcv_nxt);
2916 
2917 	db_print_indent(indent);
2918 	db_printf("rcv_adv: 0x%08x   rcv_wnd: %u   rcv_up: 0x%08x\n",
2919 	    tp->rcv_adv, tp->rcv_wnd, tp->rcv_up);
2920 
2921 	db_print_indent(indent);
2922 	db_printf("snd_wnd: %u   snd_cwnd: %u\n",
2923 	   tp->snd_wnd, tp->snd_cwnd);
2924 
2925 	db_print_indent(indent);
2926 	db_printf("snd_ssthresh: %u   snd_recover: "
2927 	    "0x%08x\n", tp->snd_ssthresh, tp->snd_recover);
2928 
2929 	db_print_indent(indent);
2930 	db_printf("t_rcvtime: %u   t_startime: %u\n",
2931 	    tp->t_rcvtime, tp->t_starttime);
2932 
2933 	db_print_indent(indent);
2934 	db_printf("t_rttime: %u   t_rtsq: 0x%08x\n",
2935 	    tp->t_rtttime, tp->t_rtseq);
2936 
2937 	db_print_indent(indent);
2938 	db_printf("t_rxtcur: %d   t_maxseg: %u   t_srtt: %d\n",
2939 	    tp->t_rxtcur, tp->t_maxseg, tp->t_srtt);
2940 
2941 	db_print_indent(indent);
2942 	db_printf("t_rttvar: %d   t_rxtshift: %d   t_rttmin: %u   "
2943 	    "t_rttbest: %u\n", tp->t_rttvar, tp->t_rxtshift, tp->t_rttmin,
2944 	    tp->t_rttbest);
2945 
2946 	db_print_indent(indent);
2947 	db_printf("t_rttupdated: %lu   max_sndwnd: %u   t_softerror: %d\n",
2948 	    tp->t_rttupdated, tp->max_sndwnd, tp->t_softerror);
2949 
2950 	db_print_indent(indent);
2951 	db_printf("t_oobflags: 0x%x (", tp->t_oobflags);
2952 	db_print_toobflags(tp->t_oobflags);
2953 	db_printf(")   t_iobc: 0x%02x\n", tp->t_iobc);
2954 
2955 	db_print_indent(indent);
2956 	db_printf("snd_scale: %u   rcv_scale: %u   request_r_scale: %u\n",
2957 	    tp->snd_scale, tp->rcv_scale, tp->request_r_scale);
2958 
2959 	db_print_indent(indent);
2960 	db_printf("ts_recent: %u   ts_recent_age: %u\n",
2961 	    tp->ts_recent, tp->ts_recent_age);
2962 
2963 	db_print_indent(indent);
2964 	db_printf("ts_offset: %u   last_ack_sent: 0x%08x   snd_cwnd_prev: "
2965 	    "%u\n", tp->ts_offset, tp->last_ack_sent, tp->snd_cwnd_prev);
2966 
2967 	db_print_indent(indent);
2968 	db_printf("snd_ssthresh_prev: %u   snd_recover_prev: 0x%08x   "
2969 	    "t_badrxtwin: %u\n", tp->snd_ssthresh_prev,
2970 	    tp->snd_recover_prev, tp->t_badrxtwin);
2971 
2972 	db_print_indent(indent);
2973 	db_printf("snd_numholes: %d  snd_holes first: %p\n",
2974 	    tp->snd_numholes, TAILQ_FIRST(&tp->snd_holes));
2975 
2976 	db_print_indent(indent);
2977 	db_printf("snd_fack: 0x%08x   rcv_numsacks: %d\n",
2978 	    tp->snd_fack, tp->rcv_numsacks);
2979 
2980 	/* Skip sackblks, sackhint. */
2981 
2982 	db_print_indent(indent);
2983 	db_printf("t_rttlow: %d   rfbuf_ts: %u   rfbuf_cnt: %d\n",
2984 	    tp->t_rttlow, tp->rfbuf_ts, tp->rfbuf_cnt);
2985 }
2986 
2987 DB_SHOW_COMMAND(tcpcb, db_show_tcpcb)
2988 {
2989 	struct tcpcb *tp;
2990 
2991 	if (!have_addr) {
2992 		db_printf("usage: show tcpcb <addr>\n");
2993 		return;
2994 	}
2995 	tp = (struct tcpcb *)addr;
2996 
2997 	db_print_tcpcb(tp, "tcpcb", 0);
2998 }
2999 #endif
3000