xref: /freebsd-13.1/sys/netinet/tcp_usrreq.c (revision f4e3cb4b)
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 		/*
326 		 * Preserve compatibility with old programs.
327 		 */
328 		if (nam->sa_family != AF_UNSPEC ||
329 		    sinp->sin_addr.s_addr != INADDR_ANY)
330 			return (EAFNOSUPPORT);
331 		nam->sa_family = AF_INET;
332 	}
333 	if (nam->sa_len != sizeof(*sinp))
334 		return (EINVAL);
335 
336 	/*
337 	 * Must check for multicast addresses and disallow binding
338 	 * to them.
339 	 */
340 	if (IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
341 		return (EAFNOSUPPORT);
342 
343 	TCPDEBUG0;
344 	inp = sotoinpcb(so);
345 	KASSERT(inp != NULL, ("tcp_usr_bind: inp == NULL"));
346 	INP_WLOCK(inp);
347 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
348 		error = EINVAL;
349 		goto out;
350 	}
351 	tp = intotcpcb(inp);
352 	TCPDEBUG1();
353 	INP_HASH_WLOCK(&V_tcbinfo);
354 	error = in_pcbbind(inp, nam, td->td_ucred);
355 	INP_HASH_WUNLOCK(&V_tcbinfo);
356 out:
357 	TCPDEBUG2(PRU_BIND);
358 	TCP_PROBE2(debug__user, tp, PRU_BIND);
359 	INP_WUNLOCK(inp);
360 
361 	return (error);
362 }
363 #endif /* INET */
364 
365 #ifdef INET6
366 static int
367 tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
368 {
369 	int error = 0;
370 	struct inpcb *inp;
371 	struct tcpcb *tp = NULL;
372 	struct sockaddr_in6 *sin6;
373 	u_char vflagsav;
374 
375 	sin6 = (struct sockaddr_in6 *)nam;
376 	if (nam->sa_family != AF_INET6)
377 		return (EAFNOSUPPORT);
378 	if (nam->sa_len != sizeof(*sin6))
379 		return (EINVAL);
380 
381 	/*
382 	 * Must check for multicast addresses and disallow binding
383 	 * to them.
384 	 */
385 	if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
386 		return (EAFNOSUPPORT);
387 
388 	TCPDEBUG0;
389 	inp = sotoinpcb(so);
390 	KASSERT(inp != NULL, ("tcp6_usr_bind: inp == NULL"));
391 	INP_WLOCK(inp);
392 	vflagsav = inp->inp_vflag;
393 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
394 		error = EINVAL;
395 		goto out;
396 	}
397 	tp = intotcpcb(inp);
398 	TCPDEBUG1();
399 	INP_HASH_WLOCK(&V_tcbinfo);
400 	inp->inp_vflag &= ~INP_IPV4;
401 	inp->inp_vflag |= INP_IPV6;
402 #ifdef INET
403 	if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
404 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr))
405 			inp->inp_vflag |= INP_IPV4;
406 		else if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
407 			struct sockaddr_in sin;
408 
409 			in6_sin6_2_sin(&sin, sin6);
410 			if (IN_MULTICAST(ntohl(sin.sin_addr.s_addr))) {
411 				error = EAFNOSUPPORT;
412 				INP_HASH_WUNLOCK(&V_tcbinfo);
413 				goto out;
414 			}
415 			inp->inp_vflag |= INP_IPV4;
416 			inp->inp_vflag &= ~INP_IPV6;
417 			error = in_pcbbind(inp, (struct sockaddr *)&sin,
418 			    td->td_ucred);
419 			INP_HASH_WUNLOCK(&V_tcbinfo);
420 			goto out;
421 		}
422 	}
423 #endif
424 	error = in6_pcbbind(inp, nam, td->td_ucred);
425 	INP_HASH_WUNLOCK(&V_tcbinfo);
426 out:
427 	if (error != 0)
428 		inp->inp_vflag = vflagsav;
429 	TCPDEBUG2(PRU_BIND);
430 	TCP_PROBE2(debug__user, tp, PRU_BIND);
431 	INP_WUNLOCK(inp);
432 	return (error);
433 }
434 #endif /* INET6 */
435 
436 #ifdef INET
437 /*
438  * Prepare to accept connections.
439  */
440 static int
441 tcp_usr_listen(struct socket *so, int backlog, struct thread *td)
442 {
443 	int error = 0;
444 	struct inpcb *inp;
445 	struct tcpcb *tp = NULL;
446 
447 	TCPDEBUG0;
448 	inp = sotoinpcb(so);
449 	KASSERT(inp != NULL, ("tcp_usr_listen: inp == NULL"));
450 	INP_WLOCK(inp);
451 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
452 		error = EINVAL;
453 		goto out;
454 	}
455 	tp = intotcpcb(inp);
456 	TCPDEBUG1();
457 	SOCK_LOCK(so);
458 	error = solisten_proto_check(so);
459 	INP_HASH_WLOCK(&V_tcbinfo);
460 	if (error == 0 && inp->inp_lport == 0)
461 		error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
462 	INP_HASH_WUNLOCK(&V_tcbinfo);
463 	if (error == 0) {
464 		tcp_state_change(tp, TCPS_LISTEN);
465 		solisten_proto(so, backlog);
466 #ifdef TCP_OFFLOAD
467 		if ((so->so_options & SO_NO_OFFLOAD) == 0)
468 			tcp_offload_listen_start(tp);
469 #endif
470 	}
471 	SOCK_UNLOCK(so);
472 
473 	if (IS_FASTOPEN(tp->t_flags))
474 		tp->t_tfo_pending = tcp_fastopen_alloc_counter();
475 
476 out:
477 	TCPDEBUG2(PRU_LISTEN);
478 	TCP_PROBE2(debug__user, tp, PRU_LISTEN);
479 	INP_WUNLOCK(inp);
480 	return (error);
481 }
482 #endif /* INET */
483 
484 #ifdef INET6
485 static int
486 tcp6_usr_listen(struct socket *so, int backlog, struct thread *td)
487 {
488 	int error = 0;
489 	struct inpcb *inp;
490 	struct tcpcb *tp = NULL;
491 	u_char vflagsav;
492 
493 	TCPDEBUG0;
494 	inp = sotoinpcb(so);
495 	KASSERT(inp != NULL, ("tcp6_usr_listen: inp == NULL"));
496 	INP_WLOCK(inp);
497 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
498 		error = EINVAL;
499 		goto out;
500 	}
501 	vflagsav = inp->inp_vflag;
502 	tp = intotcpcb(inp);
503 	TCPDEBUG1();
504 	SOCK_LOCK(so);
505 	error = solisten_proto_check(so);
506 	INP_HASH_WLOCK(&V_tcbinfo);
507 	if (error == 0 && inp->inp_lport == 0) {
508 		inp->inp_vflag &= ~INP_IPV4;
509 		if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
510 			inp->inp_vflag |= INP_IPV4;
511 		error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
512 	}
513 	INP_HASH_WUNLOCK(&V_tcbinfo);
514 	if (error == 0) {
515 		tcp_state_change(tp, TCPS_LISTEN);
516 		solisten_proto(so, backlog);
517 #ifdef TCP_OFFLOAD
518 		if ((so->so_options & SO_NO_OFFLOAD) == 0)
519 			tcp_offload_listen_start(tp);
520 #endif
521 	}
522 	SOCK_UNLOCK(so);
523 
524 	if (IS_FASTOPEN(tp->t_flags))
525 		tp->t_tfo_pending = tcp_fastopen_alloc_counter();
526 
527 	if (error != 0)
528 		inp->inp_vflag = vflagsav;
529 
530 out:
531 	TCPDEBUG2(PRU_LISTEN);
532 	TCP_PROBE2(debug__user, tp, PRU_LISTEN);
533 	INP_WUNLOCK(inp);
534 	return (error);
535 }
536 #endif /* INET6 */
537 
538 #ifdef INET
539 /*
540  * Initiate connection to peer.
541  * Create a template for use in transmissions on this connection.
542  * Enter SYN_SENT state, and mark socket as connecting.
543  * Start keep-alive timer, and seed output sequence space.
544  * Send initial segment on connection.
545  */
546 static int
547 tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
548 {
549 	struct epoch_tracker et;
550 	int error = 0;
551 	struct inpcb *inp;
552 	struct tcpcb *tp = NULL;
553 	struct sockaddr_in *sinp;
554 
555 	sinp = (struct sockaddr_in *)nam;
556 	if (nam->sa_family != AF_INET)
557 		return (EAFNOSUPPORT);
558 	if (nam->sa_len != sizeof (*sinp))
559 		return (EINVAL);
560 
561 	/*
562 	 * Must disallow TCP ``connections'' to multicast addresses.
563 	 */
564 	if (IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
565 		return (EAFNOSUPPORT);
566 	if (ntohl(sinp->sin_addr.s_addr) == INADDR_BROADCAST)
567 		return (EACCES);
568 	if ((error = prison_remote_ip4(td->td_ucred, &sinp->sin_addr)) != 0)
569 		return (error);
570 
571 	TCPDEBUG0;
572 	inp = sotoinpcb(so);
573 	KASSERT(inp != NULL, ("tcp_usr_connect: inp == NULL"));
574 	INP_WLOCK(inp);
575 	if (inp->inp_flags & INP_TIMEWAIT) {
576 		error = EADDRINUSE;
577 		goto out;
578 	}
579 	if (inp->inp_flags & INP_DROPPED) {
580 		error = ECONNREFUSED;
581 		goto out;
582 	}
583 	tp = intotcpcb(inp);
584 	TCPDEBUG1();
585 	NET_EPOCH_ENTER(et);
586 	if ((error = tcp_connect(tp, nam, td)) != 0)
587 		goto out_in_epoch;
588 #ifdef TCP_OFFLOAD
589 	if (registered_toedevs > 0 &&
590 	    (so->so_options & SO_NO_OFFLOAD) == 0 &&
591 	    (error = tcp_offload_connect(so, nam)) == 0)
592 		goto out_in_epoch;
593 #endif
594 	tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
595 	error = tp->t_fb->tfb_tcp_output(tp);
596 out_in_epoch:
597 	NET_EPOCH_EXIT(et);
598 out:
599 	TCPDEBUG2(PRU_CONNECT);
600 	TCP_PROBE2(debug__user, tp, PRU_CONNECT);
601 	INP_WUNLOCK(inp);
602 	return (error);
603 }
604 #endif /* INET */
605 
606 #ifdef INET6
607 static int
608 tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
609 {
610 	struct epoch_tracker et;
611 	int error = 0;
612 	struct inpcb *inp;
613 	struct tcpcb *tp = NULL;
614 	struct sockaddr_in6 *sin6;
615 	u_int8_t incflagsav;
616 	u_char vflagsav;
617 
618 	TCPDEBUG0;
619 
620 	sin6 = (struct sockaddr_in6 *)nam;
621 	if (nam->sa_family != AF_INET6)
622 		return (EAFNOSUPPORT);
623 	if (nam->sa_len != sizeof (*sin6))
624 		return (EINVAL);
625 
626 	/*
627 	 * Must disallow TCP ``connections'' to multicast addresses.
628 	 */
629 	if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
630 		return (EAFNOSUPPORT);
631 
632 	inp = sotoinpcb(so);
633 	KASSERT(inp != NULL, ("tcp6_usr_connect: inp == NULL"));
634 	INP_WLOCK(inp);
635 	vflagsav = inp->inp_vflag;
636 	incflagsav = inp->inp_inc.inc_flags;
637 	if (inp->inp_flags & INP_TIMEWAIT) {
638 		error = EADDRINUSE;
639 		goto out;
640 	}
641 	if (inp->inp_flags & INP_DROPPED) {
642 		error = ECONNREFUSED;
643 		goto out;
644 	}
645 	tp = intotcpcb(inp);
646 	TCPDEBUG1();
647 #ifdef INET
648 	/*
649 	 * XXXRW: Some confusion: V4/V6 flags relate to binding, and
650 	 * therefore probably require the hash lock, which isn't held here.
651 	 * Is this a significant problem?
652 	 */
653 	if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
654 		struct sockaddr_in sin;
655 
656 		if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
657 			error = EINVAL;
658 			goto out;
659 		}
660 		if ((inp->inp_vflag & INP_IPV4) == 0) {
661 			error = EAFNOSUPPORT;
662 			goto out;
663 		}
664 
665 		in6_sin6_2_sin(&sin, sin6);
666 		if (IN_MULTICAST(ntohl(sin.sin_addr.s_addr))) {
667 			error = EAFNOSUPPORT;
668 			goto out;
669 		}
670 		if (ntohl(sin.sin_addr.s_addr) == INADDR_BROADCAST) {
671 			error = EACCES;
672 			goto out;
673 		}
674 		if ((error = prison_remote_ip4(td->td_ucred,
675 		    &sin.sin_addr)) != 0)
676 			goto out;
677 		inp->inp_vflag |= INP_IPV4;
678 		inp->inp_vflag &= ~INP_IPV6;
679 		NET_EPOCH_ENTER(et);
680 		if ((error = tcp_connect(tp, (struct sockaddr *)&sin, td)) != 0)
681 			goto out_in_epoch;
682 #ifdef TCP_OFFLOAD
683 		if (registered_toedevs > 0 &&
684 		    (so->so_options & SO_NO_OFFLOAD) == 0 &&
685 		    (error = tcp_offload_connect(so, nam)) == 0)
686 			goto out_in_epoch;
687 #endif
688 		error = tp->t_fb->tfb_tcp_output(tp);
689 		goto out_in_epoch;
690 	} else {
691 		if ((inp->inp_vflag & INP_IPV6) == 0) {
692 			error = EAFNOSUPPORT;
693 			goto out;
694 		}
695 	}
696 #endif
697 	if ((error = prison_remote_ip6(td->td_ucred, &sin6->sin6_addr)) != 0)
698 		goto out;
699 	inp->inp_vflag &= ~INP_IPV4;
700 	inp->inp_vflag |= INP_IPV6;
701 	inp->inp_inc.inc_flags |= INC_ISIPV6;
702 	if ((error = tcp6_connect(tp, nam, td)) != 0)
703 		goto out;
704 #ifdef TCP_OFFLOAD
705 	if (registered_toedevs > 0 &&
706 	    (so->so_options & SO_NO_OFFLOAD) == 0 &&
707 	    (error = tcp_offload_connect(so, nam)) == 0)
708 		goto out;
709 #endif
710 	tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
711 	NET_EPOCH_ENTER(et);
712 	error = tp->t_fb->tfb_tcp_output(tp);
713 #ifdef INET
714 out_in_epoch:
715 #endif
716 	NET_EPOCH_EXIT(et);
717 out:
718 	/*
719 	 * If the implicit bind in the connect call fails, restore
720 	 * the flags we modified.
721 	 */
722 	if (error != 0 && inp->inp_lport == 0) {
723 		inp->inp_vflag = vflagsav;
724 		inp->inp_inc.inc_flags = incflagsav;
725 	}
726 
727 	TCPDEBUG2(PRU_CONNECT);
728 	TCP_PROBE2(debug__user, tp, PRU_CONNECT);
729 	INP_WUNLOCK(inp);
730 	return (error);
731 }
732 #endif /* INET6 */
733 
734 /*
735  * Initiate disconnect from peer.
736  * If connection never passed embryonic stage, just drop;
737  * else if don't need to let data drain, then can just drop anyways,
738  * else have to begin TCP shutdown process: mark socket disconnecting,
739  * drain unread data, state switch to reflect user close, and
740  * send segment (e.g. FIN) to peer.  Socket will be really disconnected
741  * when peer sends FIN and acks ours.
742  *
743  * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.
744  */
745 static int
746 tcp_usr_disconnect(struct socket *so)
747 {
748 	struct inpcb *inp;
749 	struct tcpcb *tp = NULL;
750 	struct epoch_tracker et;
751 	int error = 0;
752 
753 	TCPDEBUG0;
754 	NET_EPOCH_ENTER(et);
755 	inp = sotoinpcb(so);
756 	KASSERT(inp != NULL, ("tcp_usr_disconnect: inp == NULL"));
757 	INP_WLOCK(inp);
758 	if (inp->inp_flags & INP_TIMEWAIT)
759 		goto out;
760 	if (inp->inp_flags & INP_DROPPED) {
761 		error = ECONNRESET;
762 		goto out;
763 	}
764 	tp = intotcpcb(inp);
765 	TCPDEBUG1();
766 	tcp_disconnect(tp);
767 out:
768 	TCPDEBUG2(PRU_DISCONNECT);
769 	TCP_PROBE2(debug__user, tp, PRU_DISCONNECT);
770 	INP_WUNLOCK(inp);
771 	NET_EPOCH_EXIT(et);
772 	return (error);
773 }
774 
775 #ifdef INET
776 /*
777  * Accept a connection.  Essentially all the work is done at higher levels;
778  * just return the address of the peer, storing through addr.
779  */
780 static int
781 tcp_usr_accept(struct socket *so, struct sockaddr **nam)
782 {
783 	int error = 0;
784 	struct inpcb *inp = NULL;
785 	struct tcpcb *tp = NULL;
786 	struct in_addr addr;
787 	in_port_t port = 0;
788 	TCPDEBUG0;
789 
790 	if (so->so_state & SS_ISDISCONNECTED)
791 		return (ECONNABORTED);
792 
793 	inp = sotoinpcb(so);
794 	KASSERT(inp != NULL, ("tcp_usr_accept: inp == NULL"));
795 	INP_WLOCK(inp);
796 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
797 		error = ECONNABORTED;
798 		goto out;
799 	}
800 	tp = intotcpcb(inp);
801 	TCPDEBUG1();
802 
803 	/*
804 	 * We inline in_getpeeraddr and COMMON_END here, so that we can
805 	 * copy the data of interest and defer the malloc until after we
806 	 * release the lock.
807 	 */
808 	port = inp->inp_fport;
809 	addr = inp->inp_faddr;
810 
811 out:
812 	TCPDEBUG2(PRU_ACCEPT);
813 	TCP_PROBE2(debug__user, tp, PRU_ACCEPT);
814 	INP_WUNLOCK(inp);
815 	if (error == 0)
816 		*nam = in_sockaddr(port, &addr);
817 	return error;
818 }
819 #endif /* INET */
820 
821 #ifdef INET6
822 static int
823 tcp6_usr_accept(struct socket *so, struct sockaddr **nam)
824 {
825 	struct inpcb *inp = NULL;
826 	int error = 0;
827 	struct tcpcb *tp = NULL;
828 	struct in_addr addr;
829 	struct in6_addr addr6;
830 	struct epoch_tracker et;
831 	in_port_t port = 0;
832 	int v4 = 0;
833 	TCPDEBUG0;
834 
835 	if (so->so_state & SS_ISDISCONNECTED)
836 		return (ECONNABORTED);
837 
838 	inp = sotoinpcb(so);
839 	KASSERT(inp != NULL, ("tcp6_usr_accept: inp == NULL"));
840 	NET_EPOCH_ENTER(et);
841 	INP_WLOCK(inp);
842 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
843 		error = ECONNABORTED;
844 		goto out;
845 	}
846 	tp = intotcpcb(inp);
847 	TCPDEBUG1();
848 
849 	/*
850 	 * We inline in6_mapped_peeraddr and COMMON_END here, so that we can
851 	 * copy the data of interest and defer the malloc until after we
852 	 * release the lock.
853 	 */
854 	if (inp->inp_vflag & INP_IPV4) {
855 		v4 = 1;
856 		port = inp->inp_fport;
857 		addr = inp->inp_faddr;
858 	} else {
859 		port = inp->inp_fport;
860 		addr6 = inp->in6p_faddr;
861 	}
862 
863 out:
864 	TCPDEBUG2(PRU_ACCEPT);
865 	TCP_PROBE2(debug__user, tp, PRU_ACCEPT);
866 	INP_WUNLOCK(inp);
867 	NET_EPOCH_EXIT(et);
868 	if (error == 0) {
869 		if (v4)
870 			*nam = in6_v4mapsin6_sockaddr(port, &addr);
871 		else
872 			*nam = in6_sockaddr(port, &addr6);
873 	}
874 	return error;
875 }
876 #endif /* INET6 */
877 
878 /*
879  * Mark the connection as being incapable of further output.
880  */
881 static int
882 tcp_usr_shutdown(struct socket *so)
883 {
884 	int error = 0;
885 	struct inpcb *inp;
886 	struct tcpcb *tp = NULL;
887 	struct epoch_tracker et;
888 
889 	TCPDEBUG0;
890 	NET_EPOCH_ENTER(et);
891 	inp = sotoinpcb(so);
892 	KASSERT(inp != NULL, ("inp == NULL"));
893 	INP_WLOCK(inp);
894 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
895 		error = ECONNRESET;
896 		goto out;
897 	}
898 	tp = intotcpcb(inp);
899 	TCPDEBUG1();
900 	socantsendmore(so);
901 	tcp_usrclosed(tp);
902 	if (!(inp->inp_flags & INP_DROPPED))
903 		error = tp->t_fb->tfb_tcp_output(tp);
904 
905 out:
906 	TCPDEBUG2(PRU_SHUTDOWN);
907 	TCP_PROBE2(debug__user, tp, PRU_SHUTDOWN);
908 	INP_WUNLOCK(inp);
909 	NET_EPOCH_EXIT(et);
910 
911 	return (error);
912 }
913 
914 /*
915  * After a receive, possibly send window update to peer.
916  */
917 static int
918 tcp_usr_rcvd(struct socket *so, int flags)
919 {
920 	struct epoch_tracker et;
921 	struct inpcb *inp;
922 	struct tcpcb *tp = NULL;
923 	int error = 0;
924 
925 	TCPDEBUG0;
926 	inp = sotoinpcb(so);
927 	KASSERT(inp != NULL, ("tcp_usr_rcvd: inp == NULL"));
928 	INP_WLOCK(inp);
929 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
930 		error = ECONNRESET;
931 		goto out;
932 	}
933 	tp = intotcpcb(inp);
934 	TCPDEBUG1();
935 	/*
936 	 * For passively-created TFO connections, don't attempt a window
937 	 * update while still in SYN_RECEIVED as this may trigger an early
938 	 * SYN|ACK.  It is preferable to have the SYN|ACK be sent along with
939 	 * application response data, or failing that, when the DELACK timer
940 	 * expires.
941 	 */
942 	if (IS_FASTOPEN(tp->t_flags) &&
943 	    (tp->t_state == TCPS_SYN_RECEIVED))
944 		goto out;
945 	NET_EPOCH_ENTER(et);
946 #ifdef TCP_OFFLOAD
947 	if (tp->t_flags & TF_TOE)
948 		tcp_offload_rcvd(tp);
949 	else
950 #endif
951 	tp->t_fb->tfb_tcp_output(tp);
952 	NET_EPOCH_EXIT(et);
953 out:
954 	TCPDEBUG2(PRU_RCVD);
955 	TCP_PROBE2(debug__user, tp, PRU_RCVD);
956 	INP_WUNLOCK(inp);
957 	return (error);
958 }
959 
960 /*
961  * Do a send by putting data in output queue and updating urgent
962  * marker if URG set.  Possibly send more data.  Unlike the other
963  * pru_*() routines, the mbuf chains are our responsibility.  We
964  * must either enqueue them or free them.  The other pru_* routines
965  * generally are caller-frees.
966  */
967 static int
968 tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
969     struct sockaddr *nam, struct mbuf *control, struct thread *td)
970 {
971 	struct epoch_tracker et;
972 	int error = 0;
973 	struct inpcb *inp;
974 	struct tcpcb *tp = NULL;
975 #ifdef INET
976 #ifdef INET6
977 	struct sockaddr_in sin;
978 #endif
979 	struct sockaddr_in *sinp;
980 #endif
981 #ifdef INET6
982 	int isipv6;
983 #endif
984 	u_int8_t incflagsav;
985 	u_char vflagsav;
986 	bool restoreflags;
987 	TCPDEBUG0;
988 
989 	/*
990 	 * We require the pcbinfo "read lock" if we will close the socket
991 	 * as part of this call.
992 	 */
993 	NET_EPOCH_ENTER(et);
994 	inp = sotoinpcb(so);
995 	KASSERT(inp != NULL, ("tcp_usr_send: inp == NULL"));
996 	INP_WLOCK(inp);
997 	vflagsav = inp->inp_vflag;
998 	incflagsav = inp->inp_inc.inc_flags;
999 	restoreflags = false;
1000 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1001 		if (control)
1002 			m_freem(control);
1003 		error = ECONNRESET;
1004 		goto out;
1005 	}
1006 	if (control != NULL) {
1007 		/* TCP doesn't do control messages (rights, creds, etc) */
1008 		if (control->m_len) {
1009 			m_freem(control);
1010 			error = EINVAL;
1011 			goto out;
1012 		}
1013 		m_freem(control);	/* empty control, just free it */
1014 		control = NULL;
1015 	}
1016 	tp = intotcpcb(inp);
1017 	if ((flags & PRUS_OOB) != 0 &&
1018 	    (error = tcp_pru_options_support(tp, PRUS_OOB)) != 0)
1019 		goto out;
1020 
1021 	TCPDEBUG1();
1022 	if (nam != NULL && tp->t_state < TCPS_SYN_SENT) {
1023 		switch (nam->sa_family) {
1024 #ifdef INET
1025 		case AF_INET:
1026 			sinp = (struct sockaddr_in *)nam;
1027 			if (sinp->sin_len != sizeof(struct sockaddr_in)) {
1028 				error = EINVAL;
1029 				goto out;
1030 			}
1031 			if ((inp->inp_vflag & INP_IPV6) != 0) {
1032 				error = EAFNOSUPPORT;
1033 				goto out;
1034 			}
1035 			if (IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) {
1036 				error = EAFNOSUPPORT;
1037 				goto out;
1038 			}
1039 			if (ntohl(sinp->sin_addr.s_addr) == INADDR_BROADCAST) {
1040 				error = EACCES;
1041 				goto out;
1042 			}
1043 			if ((error = prison_remote_ip4(td->td_ucred,
1044 			    &sinp->sin_addr)))
1045 				goto out;
1046 #ifdef INET6
1047 			isipv6 = 0;
1048 #endif
1049 			break;
1050 #endif /* INET */
1051 #ifdef INET6
1052 		case AF_INET6:
1053 		{
1054 			struct sockaddr_in6 *sin6;
1055 
1056 			sin6 = (struct sockaddr_in6 *)nam;
1057 			if (sin6->sin6_len != sizeof(*sin6)) {
1058 				error = EINVAL;
1059 				goto out;
1060 			}
1061 			if ((inp->inp_vflag & INP_IPV6PROTO) == 0) {
1062 				error = EAFNOSUPPORT;
1063 				goto out;
1064 			}
1065 			if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) {
1066 				error = EAFNOSUPPORT;
1067 				goto out;
1068 			}
1069 			if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
1070 #ifdef INET
1071 				if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
1072 					error = EINVAL;
1073 					goto out;
1074 				}
1075 				if ((inp->inp_vflag & INP_IPV4) == 0) {
1076 					error = EAFNOSUPPORT;
1077 					goto out;
1078 				}
1079 				restoreflags = true;
1080 				inp->inp_vflag &= ~INP_IPV6;
1081 				sinp = &sin;
1082 				in6_sin6_2_sin(sinp, sin6);
1083 				if (IN_MULTICAST(
1084 				    ntohl(sinp->sin_addr.s_addr))) {
1085 					error = EAFNOSUPPORT;
1086 					goto out;
1087 				}
1088 				if ((error = prison_remote_ip4(td->td_ucred,
1089 				    &sinp->sin_addr)))
1090 					goto out;
1091 				isipv6 = 0;
1092 #else /* !INET */
1093 				error = EAFNOSUPPORT;
1094 				goto out;
1095 #endif /* INET */
1096 			} else {
1097 				if ((inp->inp_vflag & INP_IPV6) == 0) {
1098 					error = EAFNOSUPPORT;
1099 					goto out;
1100 				}
1101 				restoreflags = true;
1102 				inp->inp_vflag &= ~INP_IPV4;
1103 				inp->inp_inc.inc_flags |= INC_ISIPV6;
1104 				if ((error = prison_remote_ip6(td->td_ucred,
1105 				    &sin6->sin6_addr)))
1106 					goto out;
1107 				isipv6 = 1;
1108 			}
1109 			break;
1110 		}
1111 #endif /* INET6 */
1112 		default:
1113 			error = EAFNOSUPPORT;
1114 			goto out;
1115 		}
1116 	}
1117 	if (!(flags & PRUS_OOB)) {
1118 		sbappendstream(&so->so_snd, m, flags);
1119 		m = NULL;
1120 		if (nam && tp->t_state < TCPS_SYN_SENT) {
1121 			/*
1122 			 * Do implied connect if not yet connected,
1123 			 * initialize window to default value, and
1124 			 * initialize maxseg using peer's cached MSS.
1125 			 */
1126 #ifdef INET6
1127 			if (isipv6)
1128 				error = tcp6_connect(tp, nam, td);
1129 #endif /* INET6 */
1130 #if defined(INET6) && defined(INET)
1131 			else
1132 #endif
1133 #ifdef INET
1134 				error = tcp_connect(tp,
1135 				    (struct sockaddr *)sinp, td);
1136 #endif
1137 			/*
1138 			 * The bind operation in tcp_connect succeeded. We
1139 			 * no longer want to restore the flags if later
1140 			 * operations fail.
1141 			 */
1142 			if (error == 0 || inp->inp_lport != 0)
1143 				restoreflags = false;
1144 
1145 			if (error) {
1146 				/* m is freed if PRUS_NOTREADY is unset. */
1147 				sbflush(&so->so_snd);
1148 				goto out;
1149 			}
1150 			if (IS_FASTOPEN(tp->t_flags))
1151 				tcp_fastopen_connect(tp);
1152 			else {
1153 				tp->snd_wnd = TTCP_CLIENT_SND_WND;
1154 				tcp_mss(tp, -1);
1155 			}
1156 		}
1157 		if (flags & PRUS_EOF) {
1158 			/*
1159 			 * Close the send side of the connection after
1160 			 * the data is sent.
1161 			 */
1162 			socantsendmore(so);
1163 			tcp_usrclosed(tp);
1164 		}
1165 		if (TCPS_HAVEESTABLISHED(tp->t_state) &&
1166 		    ((tp->t_flags2 & TF2_FBYTES_COMPLETE) == 0) &&
1167 		    (tp->t_fbyte_out == 0) &&
1168 		    (so->so_snd.sb_ccc > 0)) {
1169 			tp->t_fbyte_out = ticks;
1170 			if (tp->t_fbyte_out == 0)
1171 				tp->t_fbyte_out = 1;
1172 			if (tp->t_fbyte_out && tp->t_fbyte_in)
1173 				tp->t_flags2 |= TF2_FBYTES_COMPLETE;
1174 		}
1175 		if (!(inp->inp_flags & INP_DROPPED) &&
1176 		    !(flags & PRUS_NOTREADY)) {
1177 			if (flags & PRUS_MORETOCOME)
1178 				tp->t_flags |= TF_MORETOCOME;
1179 			error = tp->t_fb->tfb_tcp_output(tp);
1180 			if (flags & PRUS_MORETOCOME)
1181 				tp->t_flags &= ~TF_MORETOCOME;
1182 		}
1183 	} else {
1184 		/*
1185 		 * XXXRW: PRUS_EOF not implemented with PRUS_OOB?
1186 		 */
1187 		SOCKBUF_LOCK(&so->so_snd);
1188 		if (sbspace(&so->so_snd) < -512) {
1189 			SOCKBUF_UNLOCK(&so->so_snd);
1190 			error = ENOBUFS;
1191 			goto out;
1192 		}
1193 		/*
1194 		 * According to RFC961 (Assigned Protocols),
1195 		 * the urgent pointer points to the last octet
1196 		 * of urgent data.  We continue, however,
1197 		 * to consider it to indicate the first octet
1198 		 * of data past the urgent section.
1199 		 * Otherwise, snd_up should be one lower.
1200 		 */
1201 		sbappendstream_locked(&so->so_snd, m, flags);
1202 		SOCKBUF_UNLOCK(&so->so_snd);
1203 		m = NULL;
1204 		if (nam && tp->t_state < TCPS_SYN_SENT) {
1205 			/*
1206 			 * Do implied connect if not yet connected,
1207 			 * initialize window to default value, and
1208 			 * initialize maxseg using peer's cached MSS.
1209 			 */
1210 
1211 			/*
1212 			 * Not going to contemplate SYN|URG
1213 			 */
1214 			if (IS_FASTOPEN(tp->t_flags))
1215 				tp->t_flags &= ~TF_FASTOPEN;
1216 #ifdef INET6
1217 			if (isipv6)
1218 				error = tcp6_connect(tp, nam, td);
1219 #endif /* INET6 */
1220 #if defined(INET6) && defined(INET)
1221 			else
1222 #endif
1223 #ifdef INET
1224 				error = tcp_connect(tp,
1225 				    (struct sockaddr *)sinp, td);
1226 #endif
1227 			/*
1228 			 * The bind operation in tcp_connect succeeded. We
1229 			 * no longer want to restore the flags if later
1230 			 * operations fail.
1231 			 */
1232 			if (error == 0 || inp->inp_lport != 0)
1233 				restoreflags = false;
1234 
1235 			if (error != 0) {
1236 				/* m is freed if PRUS_NOTREADY is unset. */
1237 				sbflush(&so->so_snd);
1238 				goto out;
1239 			}
1240 			tp->snd_wnd = TTCP_CLIENT_SND_WND;
1241 			tcp_mss(tp, -1);
1242 		}
1243 		tp->snd_up = tp->snd_una + sbavail(&so->so_snd);
1244 		if ((flags & PRUS_NOTREADY) == 0) {
1245 			tp->t_flags |= TF_FORCEDATA;
1246 			error = tp->t_fb->tfb_tcp_output(tp);
1247 			tp->t_flags &= ~TF_FORCEDATA;
1248 		}
1249 	}
1250 	TCP_LOG_EVENT(tp, NULL,
1251 	    &inp->inp_socket->so_rcv,
1252 	    &inp->inp_socket->so_snd,
1253 	    TCP_LOG_USERSEND, error,
1254 	    0, NULL, false);
1255 
1256 out:
1257 	/*
1258 	 * In case of PRUS_NOTREADY, the caller or tcp_usr_ready() is
1259 	 * responsible for freeing memory.
1260 	 */
1261 	if (m != NULL && (flags & PRUS_NOTREADY) == 0)
1262 		m_freem(m);
1263 
1264 	/*
1265 	 * If the request was unsuccessful and we changed flags,
1266 	 * restore the original flags.
1267 	 */
1268 	if (error != 0 && restoreflags) {
1269 		inp->inp_vflag = vflagsav;
1270 		inp->inp_inc.inc_flags = incflagsav;
1271 	}
1272 	TCPDEBUG2((flags & PRUS_OOB) ? PRU_SENDOOB :
1273 		  ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
1274 	TCP_PROBE2(debug__user, tp, (flags & PRUS_OOB) ? PRU_SENDOOB :
1275 		   ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
1276 	INP_WUNLOCK(inp);
1277 	NET_EPOCH_EXIT(et);
1278 	return (error);
1279 }
1280 
1281 static int
1282 tcp_usr_ready(struct socket *so, struct mbuf *m, int count)
1283 {
1284 	struct epoch_tracker et;
1285 	struct inpcb *inp;
1286 	struct tcpcb *tp;
1287 	int error;
1288 
1289 	inp = sotoinpcb(so);
1290 	INP_WLOCK(inp);
1291 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1292 		INP_WUNLOCK(inp);
1293 		mb_free_notready(m, count);
1294 		return (ECONNRESET);
1295 	}
1296 	tp = intotcpcb(inp);
1297 
1298 	SOCKBUF_LOCK(&so->so_snd);
1299 	error = sbready(&so->so_snd, m, count);
1300 	SOCKBUF_UNLOCK(&so->so_snd);
1301 	if (error == 0) {
1302 		NET_EPOCH_ENTER(et);
1303 		error = tp->t_fb->tfb_tcp_output(tp);
1304 		NET_EPOCH_EXIT(et);
1305 	}
1306 	INP_WUNLOCK(inp);
1307 
1308 	return (error);
1309 }
1310 
1311 /*
1312  * Abort the TCP.  Drop the connection abruptly.
1313  */
1314 static void
1315 tcp_usr_abort(struct socket *so)
1316 {
1317 	struct inpcb *inp;
1318 	struct tcpcb *tp = NULL;
1319 	struct epoch_tracker et;
1320 	TCPDEBUG0;
1321 
1322 	inp = sotoinpcb(so);
1323 	KASSERT(inp != NULL, ("tcp_usr_abort: inp == NULL"));
1324 
1325 	NET_EPOCH_ENTER(et);
1326 	INP_WLOCK(inp);
1327 	KASSERT(inp->inp_socket != NULL,
1328 	    ("tcp_usr_abort: inp_socket == NULL"));
1329 
1330 	/*
1331 	 * If we still have full TCP state, and we're not dropped, drop.
1332 	 */
1333 	if (!(inp->inp_flags & INP_TIMEWAIT) &&
1334 	    !(inp->inp_flags & INP_DROPPED)) {
1335 		tp = intotcpcb(inp);
1336 		TCPDEBUG1();
1337 		tp = tcp_drop(tp, ECONNABORTED);
1338 		if (tp == NULL)
1339 			goto dropped;
1340 		TCPDEBUG2(PRU_ABORT);
1341 		TCP_PROBE2(debug__user, tp, PRU_ABORT);
1342 	}
1343 	if (!(inp->inp_flags & INP_DROPPED)) {
1344 		SOCK_LOCK(so);
1345 		so->so_state |= SS_PROTOREF;
1346 		SOCK_UNLOCK(so);
1347 		inp->inp_flags |= INP_SOCKREF;
1348 	}
1349 	INP_WUNLOCK(inp);
1350 dropped:
1351 	NET_EPOCH_EXIT(et);
1352 }
1353 
1354 /*
1355  * TCP socket is closed.  Start friendly disconnect.
1356  */
1357 static void
1358 tcp_usr_close(struct socket *so)
1359 {
1360 	struct inpcb *inp;
1361 	struct tcpcb *tp = NULL;
1362 	struct epoch_tracker et;
1363 	TCPDEBUG0;
1364 
1365 	inp = sotoinpcb(so);
1366 	KASSERT(inp != NULL, ("tcp_usr_close: inp == NULL"));
1367 
1368 	NET_EPOCH_ENTER(et);
1369 	INP_WLOCK(inp);
1370 	KASSERT(inp->inp_socket != NULL,
1371 	    ("tcp_usr_close: inp_socket == NULL"));
1372 
1373 	/*
1374 	 * If we still have full TCP state, and we're not dropped, initiate
1375 	 * a disconnect.
1376 	 */
1377 	if (!(inp->inp_flags & INP_TIMEWAIT) &&
1378 	    !(inp->inp_flags & INP_DROPPED)) {
1379 		tp = intotcpcb(inp);
1380 		TCPDEBUG1();
1381 		tcp_disconnect(tp);
1382 		TCPDEBUG2(PRU_CLOSE);
1383 		TCP_PROBE2(debug__user, tp, PRU_CLOSE);
1384 	}
1385 	if (!(inp->inp_flags & INP_DROPPED)) {
1386 		SOCK_LOCK(so);
1387 		so->so_state |= SS_PROTOREF;
1388 		SOCK_UNLOCK(so);
1389 		inp->inp_flags |= INP_SOCKREF;
1390 	}
1391 	INP_WUNLOCK(inp);
1392 	NET_EPOCH_EXIT(et);
1393 }
1394 
1395 static int
1396 tcp_pru_options_support(struct tcpcb *tp, int flags)
1397 {
1398 	/*
1399 	 * If the specific TCP stack has a pru_options
1400 	 * specified then it does not always support
1401 	 * all the PRU_XX options and we must ask it.
1402 	 * If the function is not specified then all
1403 	 * of the PRU_XX options are supported.
1404 	 */
1405 	int ret = 0;
1406 
1407 	if (tp->t_fb->tfb_pru_options) {
1408 		ret = (*tp->t_fb->tfb_pru_options)(tp, flags);
1409 	}
1410 	return (ret);
1411 }
1412 
1413 /*
1414  * Receive out-of-band data.
1415  */
1416 static int
1417 tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags)
1418 {
1419 	int error = 0;
1420 	struct inpcb *inp;
1421 	struct tcpcb *tp = NULL;
1422 
1423 	TCPDEBUG0;
1424 	inp = sotoinpcb(so);
1425 	KASSERT(inp != NULL, ("tcp_usr_rcvoob: inp == NULL"));
1426 	INP_WLOCK(inp);
1427 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1428 		error = ECONNRESET;
1429 		goto out;
1430 	}
1431 	tp = intotcpcb(inp);
1432 	error = tcp_pru_options_support(tp, PRUS_OOB);
1433 	if (error) {
1434 		goto out;
1435 	}
1436 	TCPDEBUG1();
1437 	if ((so->so_oobmark == 0 &&
1438 	     (so->so_rcv.sb_state & SBS_RCVATMARK) == 0) ||
1439 	    so->so_options & SO_OOBINLINE ||
1440 	    tp->t_oobflags & TCPOOB_HADDATA) {
1441 		error = EINVAL;
1442 		goto out;
1443 	}
1444 	if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
1445 		error = EWOULDBLOCK;
1446 		goto out;
1447 	}
1448 	m->m_len = 1;
1449 	*mtod(m, caddr_t) = tp->t_iobc;
1450 	if ((flags & MSG_PEEK) == 0)
1451 		tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
1452 
1453 out:
1454 	TCPDEBUG2(PRU_RCVOOB);
1455 	TCP_PROBE2(debug__user, tp, PRU_RCVOOB);
1456 	INP_WUNLOCK(inp);
1457 	return (error);
1458 }
1459 
1460 #ifdef INET
1461 struct pr_usrreqs tcp_usrreqs = {
1462 	.pru_abort =		tcp_usr_abort,
1463 	.pru_accept =		tcp_usr_accept,
1464 	.pru_attach =		tcp_usr_attach,
1465 	.pru_bind =		tcp_usr_bind,
1466 	.pru_connect =		tcp_usr_connect,
1467 	.pru_control =		in_control,
1468 	.pru_detach =		tcp_usr_detach,
1469 	.pru_disconnect =	tcp_usr_disconnect,
1470 	.pru_listen =		tcp_usr_listen,
1471 	.pru_peeraddr =		in_getpeeraddr,
1472 	.pru_rcvd =		tcp_usr_rcvd,
1473 	.pru_rcvoob =		tcp_usr_rcvoob,
1474 	.pru_send =		tcp_usr_send,
1475 	.pru_ready =		tcp_usr_ready,
1476 	.pru_shutdown =		tcp_usr_shutdown,
1477 	.pru_sockaddr =		in_getsockaddr,
1478 	.pru_sosetlabel =	in_pcbsosetlabel,
1479 	.pru_close =		tcp_usr_close,
1480 };
1481 #endif /* INET */
1482 
1483 #ifdef INET6
1484 struct pr_usrreqs tcp6_usrreqs = {
1485 	.pru_abort =		tcp_usr_abort,
1486 	.pru_accept =		tcp6_usr_accept,
1487 	.pru_attach =		tcp_usr_attach,
1488 	.pru_bind =		tcp6_usr_bind,
1489 	.pru_connect =		tcp6_usr_connect,
1490 	.pru_control =		in6_control,
1491 	.pru_detach =		tcp_usr_detach,
1492 	.pru_disconnect =	tcp_usr_disconnect,
1493 	.pru_listen =		tcp6_usr_listen,
1494 	.pru_peeraddr =		in6_mapped_peeraddr,
1495 	.pru_rcvd =		tcp_usr_rcvd,
1496 	.pru_rcvoob =		tcp_usr_rcvoob,
1497 	.pru_send =		tcp_usr_send,
1498 	.pru_ready =		tcp_usr_ready,
1499 	.pru_shutdown =		tcp_usr_shutdown,
1500 	.pru_sockaddr =		in6_mapped_sockaddr,
1501 	.pru_sosetlabel =	in_pcbsosetlabel,
1502 	.pru_close =		tcp_usr_close,
1503 };
1504 #endif /* INET6 */
1505 
1506 #ifdef INET
1507 /*
1508  * Common subroutine to open a TCP connection to remote host specified
1509  * by struct sockaddr_in in mbuf *nam.  Call in_pcbbind to assign a local
1510  * port number if needed.  Call in_pcbconnect_setup to do the routing and
1511  * to choose a local host address (interface).  If there is an existing
1512  * incarnation of the same connection in TIME-WAIT state and if the remote
1513  * host was sending CC options and if the connection duration was < MSL, then
1514  * truncate the previous TIME-WAIT state and proceed.
1515  * Initialize connection parameters and enter SYN-SENT state.
1516  */
1517 static int
1518 tcp_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1519 {
1520 	struct inpcb *inp = tp->t_inpcb, *oinp;
1521 	struct socket *so = inp->inp_socket;
1522 	struct in_addr laddr;
1523 	u_short lport;
1524 	int error;
1525 
1526 	NET_EPOCH_ASSERT();
1527 	INP_WLOCK_ASSERT(inp);
1528 	INP_HASH_WLOCK(&V_tcbinfo);
1529 
1530 	if (V_tcp_require_unique_port && inp->inp_lport == 0) {
1531 		error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1532 		if (error)
1533 			goto out;
1534 	}
1535 
1536 	/*
1537 	 * Cannot simply call in_pcbconnect, because there might be an
1538 	 * earlier incarnation of this same connection still in
1539 	 * TIME_WAIT state, creating an ADDRINUSE error.
1540 	 */
1541 	laddr = inp->inp_laddr;
1542 	lport = inp->inp_lport;
1543 	error = in_pcbconnect_setup(inp, nam, &laddr.s_addr, &lport,
1544 	    &inp->inp_faddr.s_addr, &inp->inp_fport, &oinp, td->td_ucred);
1545 	if (error && oinp == NULL)
1546 		goto out;
1547 	if (oinp) {
1548 		error = EADDRINUSE;
1549 		goto out;
1550 	}
1551 	/* Handle initial bind if it hadn't been done in advance. */
1552 	if (inp->inp_lport == 0) {
1553 		inp->inp_lport = lport;
1554 		if (in_pcbinshash(inp) != 0) {
1555 			inp->inp_lport = 0;
1556 			error = EAGAIN;
1557 			goto out;
1558 		}
1559 	}
1560 	inp->inp_laddr = laddr;
1561 	in_pcbrehash(inp);
1562 	INP_HASH_WUNLOCK(&V_tcbinfo);
1563 
1564 	/*
1565 	 * Compute window scaling to request:
1566 	 * Scale to fit into sweet spot.  See tcp_syncache.c.
1567 	 * XXX: This should move to tcp_output().
1568 	 */
1569 	while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1570 	    (TCP_MAXWIN << tp->request_r_scale) < sb_max)
1571 		tp->request_r_scale++;
1572 
1573 	soisconnecting(so);
1574 	TCPSTAT_INC(tcps_connattempt);
1575 	tcp_state_change(tp, TCPS_SYN_SENT);
1576 	tp->iss = tcp_new_isn(&inp->inp_inc);
1577 	if (tp->t_flags & TF_REQ_TSTMP)
1578 		tp->ts_offset = tcp_new_ts_offset(&inp->inp_inc);
1579 	tcp_sendseqinit(tp);
1580 
1581 	return 0;
1582 
1583 out:
1584 	INP_HASH_WUNLOCK(&V_tcbinfo);
1585 	return (error);
1586 }
1587 #endif /* INET */
1588 
1589 #ifdef INET6
1590 static int
1591 tcp6_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1592 {
1593 	struct inpcb *inp = tp->t_inpcb;
1594 	int error;
1595 
1596 	INP_WLOCK_ASSERT(inp);
1597 	INP_HASH_WLOCK(&V_tcbinfo);
1598 
1599 	if (V_tcp_require_unique_port && inp->inp_lport == 0) {
1600 		error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1601 		if (error)
1602 			goto out;
1603 	}
1604 	error = in6_pcbconnect(inp, nam, td->td_ucred);
1605 	if (error != 0)
1606 		goto out;
1607 	INP_HASH_WUNLOCK(&V_tcbinfo);
1608 
1609 	/* Compute window scaling to request.  */
1610 	while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1611 	    (TCP_MAXWIN << tp->request_r_scale) < sb_max)
1612 		tp->request_r_scale++;
1613 
1614 	soisconnecting(inp->inp_socket);
1615 	TCPSTAT_INC(tcps_connattempt);
1616 	tcp_state_change(tp, TCPS_SYN_SENT);
1617 	tp->iss = tcp_new_isn(&inp->inp_inc);
1618 	if (tp->t_flags & TF_REQ_TSTMP)
1619 		tp->ts_offset = tcp_new_ts_offset(&inp->inp_inc);
1620 	tcp_sendseqinit(tp);
1621 
1622 	return 0;
1623 
1624 out:
1625 	INP_HASH_WUNLOCK(&V_tcbinfo);
1626 	return error;
1627 }
1628 #endif /* INET6 */
1629 
1630 /*
1631  * Export TCP internal state information via a struct tcp_info, based on the
1632  * Linux 2.6 API.  Not ABI compatible as our constants are mapped differently
1633  * (TCP state machine, etc).  We export all information using FreeBSD-native
1634  * constants -- for example, the numeric values for tcpi_state will differ
1635  * from Linux.
1636  */
1637 static void
1638 tcp_fill_info(struct tcpcb *tp, struct tcp_info *ti)
1639 {
1640 
1641 	INP_WLOCK_ASSERT(tp->t_inpcb);
1642 	bzero(ti, sizeof(*ti));
1643 
1644 	ti->tcpi_state = tp->t_state;
1645 	if ((tp->t_flags & TF_REQ_TSTMP) && (tp->t_flags & TF_RCVD_TSTMP))
1646 		ti->tcpi_options |= TCPI_OPT_TIMESTAMPS;
1647 	if (tp->t_flags & TF_SACK_PERMIT)
1648 		ti->tcpi_options |= TCPI_OPT_SACK;
1649 	if ((tp->t_flags & TF_REQ_SCALE) && (tp->t_flags & TF_RCVD_SCALE)) {
1650 		ti->tcpi_options |= TCPI_OPT_WSCALE;
1651 		ti->tcpi_snd_wscale = tp->snd_scale;
1652 		ti->tcpi_rcv_wscale = tp->rcv_scale;
1653 	}
1654 	if (tp->t_flags2 & TF2_ECN_PERMIT)
1655 		ti->tcpi_options |= TCPI_OPT_ECN;
1656 
1657 	ti->tcpi_rto = tp->t_rxtcur * tick;
1658 	ti->tcpi_last_data_recv = ((uint32_t)ticks - tp->t_rcvtime) * tick;
1659 	ti->tcpi_rtt = ((u_int64_t)tp->t_srtt * tick) >> TCP_RTT_SHIFT;
1660 	ti->tcpi_rttvar = ((u_int64_t)tp->t_rttvar * tick) >> TCP_RTTVAR_SHIFT;
1661 
1662 	ti->tcpi_snd_ssthresh = tp->snd_ssthresh;
1663 	ti->tcpi_snd_cwnd = tp->snd_cwnd;
1664 
1665 	/*
1666 	 * FreeBSD-specific extension fields for tcp_info.
1667 	 */
1668 	ti->tcpi_rcv_space = tp->rcv_wnd;
1669 	ti->tcpi_rcv_nxt = tp->rcv_nxt;
1670 	ti->tcpi_snd_wnd = tp->snd_wnd;
1671 	ti->tcpi_snd_bwnd = 0;		/* Unused, kept for compat. */
1672 	ti->tcpi_snd_nxt = tp->snd_nxt;
1673 	ti->tcpi_snd_mss = tp->t_maxseg;
1674 	ti->tcpi_rcv_mss = tp->t_maxseg;
1675 	ti->tcpi_snd_rexmitpack = tp->t_sndrexmitpack;
1676 	ti->tcpi_rcv_ooopack = tp->t_rcvoopack;
1677 	ti->tcpi_snd_zerowin = tp->t_sndzerowin;
1678 #ifdef TCP_OFFLOAD
1679 	if (tp->t_flags & TF_TOE) {
1680 		ti->tcpi_options |= TCPI_OPT_TOE;
1681 		tcp_offload_tcp_info(tp, ti);
1682 	}
1683 #endif
1684 }
1685 
1686 /*
1687  * tcp_ctloutput() must drop the inpcb lock before performing copyin on
1688  * socket option arguments.  When it re-acquires the lock after the copy, it
1689  * has to revalidate that the connection is still valid for the socket
1690  * option.
1691  */
1692 #define INP_WLOCK_RECHECK_CLEANUP(inp, cleanup) do {			\
1693 	INP_WLOCK(inp);							\
1694 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {		\
1695 		INP_WUNLOCK(inp);					\
1696 		cleanup;						\
1697 		return (ECONNRESET);					\
1698 	}								\
1699 	tp = intotcpcb(inp);						\
1700 } while(0)
1701 #define INP_WLOCK_RECHECK(inp) INP_WLOCK_RECHECK_CLEANUP((inp), /* noop */)
1702 
1703 int
1704 tcp_ctloutput(struct socket *so, struct sockopt *sopt)
1705 {
1706 	int	error;
1707 	struct	inpcb *inp;
1708 	struct	tcpcb *tp;
1709 	struct tcp_function_block *blk;
1710 	struct tcp_function_set fsn;
1711 
1712 	error = 0;
1713 	inp = sotoinpcb(so);
1714 	KASSERT(inp != NULL, ("tcp_ctloutput: inp == NULL"));
1715 	if (sopt->sopt_level != IPPROTO_TCP) {
1716 #ifdef INET6
1717 		if (inp->inp_vflag & INP_IPV6PROTO) {
1718 			error = ip6_ctloutput(so, sopt);
1719 			/*
1720 			 * In case of the IPV6_USE_MIN_MTU socket option,
1721 			 * the INC_IPV6MINMTU flag to announce a corresponding
1722 			 * MSS during the initial handshake.
1723 			 * If the TCP connection is not in the front states,
1724 			 * just reduce the MSS being used.
1725 			 * This avoids the sending of TCP segments which will
1726 			 * be fragmented at the IPv6 layer.
1727 			 */
1728 			if ((error == 0) &&
1729 			    (sopt->sopt_dir == SOPT_SET) &&
1730 			    (sopt->sopt_level == IPPROTO_IPV6) &&
1731 			    (sopt->sopt_name == IPV6_USE_MIN_MTU)) {
1732 				INP_WLOCK(inp);
1733 				if ((inp->inp_flags &
1734 				    (INP_TIMEWAIT | INP_DROPPED))) {
1735 					INP_WUNLOCK(inp);
1736 					return (ECONNRESET);
1737 				}
1738 				inp->inp_inc.inc_flags |= INC_IPV6MINMTU;
1739 				tp = intotcpcb(inp);
1740 				if ((tp->t_state >= TCPS_SYN_SENT) &&
1741 				    (inp->inp_inc.inc_flags & INC_ISIPV6)) {
1742 					struct ip6_pktopts *opt;
1743 
1744 					opt = inp->in6p_outputopts;
1745 					if ((opt != NULL) &&
1746 					    (opt->ip6po_minmtu ==
1747 					    IP6PO_MINMTU_ALL)) {
1748 						if (tp->t_maxseg > TCP6_MSS) {
1749 							tp->t_maxseg = TCP6_MSS;
1750 						}
1751 					}
1752 				}
1753 				INP_WUNLOCK(inp);
1754 			}
1755 		}
1756 #endif /* INET6 */
1757 #if defined(INET6) && defined(INET)
1758 		else
1759 #endif
1760 #ifdef INET
1761 		{
1762 			error = ip_ctloutput(so, sopt);
1763 		}
1764 #endif
1765 		return (error);
1766 	}
1767 	INP_WLOCK(inp);
1768 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1769 		INP_WUNLOCK(inp);
1770 		return (ECONNRESET);
1771 	}
1772 	tp = intotcpcb(inp);
1773 	/*
1774 	 * Protect the TCP option TCP_FUNCTION_BLK so
1775 	 * that a sub-function can *never* overwrite this.
1776 	 */
1777 	if ((sopt->sopt_dir == SOPT_SET) &&
1778 	    (sopt->sopt_name == TCP_FUNCTION_BLK)) {
1779 		INP_WUNLOCK(inp);
1780 		error = sooptcopyin(sopt, &fsn, sizeof fsn,
1781 		    sizeof fsn);
1782 		if (error)
1783 			return (error);
1784 		INP_WLOCK_RECHECK(inp);
1785 		blk = find_and_ref_tcp_functions(&fsn);
1786 		if (blk == NULL) {
1787 			INP_WUNLOCK(inp);
1788 			return (ENOENT);
1789 		}
1790 		if (tp->t_fb == blk) {
1791 			/* You already have this */
1792 			refcount_release(&blk->tfb_refcnt);
1793 			INP_WUNLOCK(inp);
1794 			return (0);
1795 		}
1796 		if (tp->t_state != TCPS_CLOSED) {
1797 			/*
1798 			 * The user has advanced the state
1799 			 * past the initial point, we may not
1800 			 * be able to switch.
1801 			 */
1802 			if (blk->tfb_tcp_handoff_ok != NULL) {
1803 				/*
1804 				 * Does the stack provide a
1805 				 * query mechanism, if so it may
1806 				 * still be possible?
1807 				 */
1808 				error = (*blk->tfb_tcp_handoff_ok)(tp);
1809 			} else
1810 				error = EINVAL;
1811 			if (error) {
1812 				refcount_release(&blk->tfb_refcnt);
1813 				INP_WUNLOCK(inp);
1814 				return(error);
1815 			}
1816 		}
1817 		if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) {
1818 			refcount_release(&blk->tfb_refcnt);
1819 			INP_WUNLOCK(inp);
1820 			return (ENOENT);
1821 		}
1822 		/*
1823 		 * Release the old refcnt, the
1824 		 * lookup acquired a ref on the
1825 		 * new one already.
1826 		 */
1827 		if (tp->t_fb->tfb_tcp_fb_fini) {
1828 			struct epoch_tracker et;
1829 			/*
1830 			 * Tell the stack to cleanup with 0 i.e.
1831 			 * the tcb is not going away.
1832 			 */
1833 			NET_EPOCH_ENTER(et);
1834 			(*tp->t_fb->tfb_tcp_fb_fini)(tp, 0);
1835 			NET_EPOCH_EXIT(et);
1836 		}
1837 #ifdef TCPHPTS
1838 		/* Assure that we are not on any hpts */
1839 		tcp_hpts_remove(tp->t_inpcb, HPTS_REMOVE_ALL);
1840 #endif
1841 		if (blk->tfb_tcp_fb_init) {
1842 			error = (*blk->tfb_tcp_fb_init)(tp);
1843 			if (error) {
1844 				refcount_release(&blk->tfb_refcnt);
1845 				if (tp->t_fb->tfb_tcp_fb_init) {
1846 					if((*tp->t_fb->tfb_tcp_fb_init)(tp) != 0)  {
1847 						/* Fall back failed, drop the connection */
1848 						INP_WUNLOCK(inp);
1849 						soabort(so);
1850 						return(error);
1851 					}
1852 				}
1853 				goto err_out;
1854 			}
1855 		}
1856 		refcount_release(&tp->t_fb->tfb_refcnt);
1857 		tp->t_fb = blk;
1858 #ifdef TCP_OFFLOAD
1859 		if (tp->t_flags & TF_TOE) {
1860 			tcp_offload_ctloutput(tp, sopt->sopt_dir,
1861 			     sopt->sopt_name);
1862 		}
1863 #endif
1864 err_out:
1865 		INP_WUNLOCK(inp);
1866 		return (error);
1867 	} else if ((sopt->sopt_dir == SOPT_GET) &&
1868 	    (sopt->sopt_name == TCP_FUNCTION_BLK)) {
1869 		strncpy(fsn.function_set_name, tp->t_fb->tfb_tcp_block_name,
1870 		    TCP_FUNCTION_NAME_LEN_MAX);
1871 		fsn.function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0';
1872 		fsn.pcbcnt = tp->t_fb->tfb_refcnt;
1873 		INP_WUNLOCK(inp);
1874 		error = sooptcopyout(sopt, &fsn, sizeof fsn);
1875 		return (error);
1876 	}
1877 	/* Pass in the INP locked, called must unlock it */
1878 	return (tp->t_fb->tfb_tcp_ctloutput(so, sopt, inp, tp));
1879 }
1880 
1881 /*
1882  * If this assert becomes untrue, we need to change the size of the buf
1883  * variable in tcp_default_ctloutput().
1884  */
1885 #ifdef CTASSERT
1886 CTASSERT(TCP_CA_NAME_MAX <= TCP_LOG_ID_LEN);
1887 CTASSERT(TCP_LOG_REASON_LEN <= TCP_LOG_ID_LEN);
1888 #endif
1889 
1890 #ifdef KERN_TLS
1891 static int
1892 copyin_tls_enable(struct sockopt *sopt, struct tls_enable *tls)
1893 {
1894 	struct tls_enable_v0 tls_v0;
1895 	int error;
1896 
1897 	if (sopt->sopt_valsize == sizeof(tls_v0)) {
1898 		error = sooptcopyin(sopt, &tls_v0, sizeof(tls_v0),
1899 		    sizeof(tls_v0));
1900 		if (error)
1901 			return (error);
1902 		memset(tls, 0, sizeof(*tls));
1903 		tls->cipher_key = tls_v0.cipher_key;
1904 		tls->iv = tls_v0.iv;
1905 		tls->auth_key = tls_v0.auth_key;
1906 		tls->cipher_algorithm = tls_v0.cipher_algorithm;
1907 		tls->cipher_key_len = tls_v0.cipher_key_len;
1908 		tls->iv_len = tls_v0.iv_len;
1909 		tls->auth_algorithm = tls_v0.auth_algorithm;
1910 		tls->auth_key_len = tls_v0.auth_key_len;
1911 		tls->flags = tls_v0.flags;
1912 		tls->tls_vmajor = tls_v0.tls_vmajor;
1913 		tls->tls_vminor = tls_v0.tls_vminor;
1914 		return (0);
1915 	}
1916 
1917 	return (sooptcopyin(sopt, tls, sizeof(*tls), sizeof(*tls)));
1918 }
1919 #endif
1920 
1921 int
1922 tcp_default_ctloutput(struct socket *so, struct sockopt *sopt, struct inpcb *inp, struct tcpcb *tp)
1923 {
1924 	int	error, opt, optval;
1925 	u_int	ui;
1926 	struct	tcp_info ti;
1927 #ifdef KERN_TLS
1928 	struct tls_enable tls;
1929 #endif
1930 	struct cc_algo *algo;
1931 	char	*pbuf, buf[TCP_LOG_ID_LEN];
1932 #ifdef STATS
1933 	struct statsblob *sbp;
1934 #endif
1935 	size_t	len;
1936 
1937 	/*
1938 	 * For TCP_CCALGOOPT forward the control to CC module, for both
1939 	 * SOPT_SET and SOPT_GET.
1940 	 */
1941 	switch (sopt->sopt_name) {
1942 	case TCP_CCALGOOPT:
1943 		INP_WUNLOCK(inp);
1944 		if (sopt->sopt_valsize > CC_ALGOOPT_LIMIT)
1945 			return (EINVAL);
1946 		pbuf = malloc(sopt->sopt_valsize, M_TEMP, M_WAITOK | M_ZERO);
1947 		error = sooptcopyin(sopt, pbuf, sopt->sopt_valsize,
1948 		    sopt->sopt_valsize);
1949 		if (error) {
1950 			free(pbuf, M_TEMP);
1951 			return (error);
1952 		}
1953 		INP_WLOCK_RECHECK_CLEANUP(inp, free(pbuf, M_TEMP));
1954 		if (CC_ALGO(tp)->ctl_output != NULL)
1955 			error = CC_ALGO(tp)->ctl_output(tp->ccv, sopt, pbuf);
1956 		else
1957 			error = ENOENT;
1958 		INP_WUNLOCK(inp);
1959 		if (error == 0 && sopt->sopt_dir == SOPT_GET)
1960 			error = sooptcopyout(sopt, pbuf, sopt->sopt_valsize);
1961 		free(pbuf, M_TEMP);
1962 		return (error);
1963 	}
1964 
1965 	switch (sopt->sopt_dir) {
1966 	case SOPT_SET:
1967 		switch (sopt->sopt_name) {
1968 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
1969 		case TCP_MD5SIG:
1970 			if (!TCPMD5_ENABLED()) {
1971 				INP_WUNLOCK(inp);
1972 				return (ENOPROTOOPT);
1973 			}
1974 			error = TCPMD5_PCBCTL(inp, sopt);
1975 			if (error)
1976 				return (error);
1977 			goto unlock_and_done;
1978 #endif /* IPSEC */
1979 
1980 		case TCP_NODELAY:
1981 		case TCP_NOOPT:
1982 			INP_WUNLOCK(inp);
1983 			error = sooptcopyin(sopt, &optval, sizeof optval,
1984 			    sizeof optval);
1985 			if (error)
1986 				return (error);
1987 
1988 			INP_WLOCK_RECHECK(inp);
1989 			switch (sopt->sopt_name) {
1990 			case TCP_NODELAY:
1991 				opt = TF_NODELAY;
1992 				break;
1993 			case TCP_NOOPT:
1994 				opt = TF_NOOPT;
1995 				break;
1996 			default:
1997 				opt = 0; /* dead code to fool gcc */
1998 				break;
1999 			}
2000 
2001 			if (optval)
2002 				tp->t_flags |= opt;
2003 			else
2004 				tp->t_flags &= ~opt;
2005 unlock_and_done:
2006 #ifdef TCP_OFFLOAD
2007 			if (tp->t_flags & TF_TOE) {
2008 				tcp_offload_ctloutput(tp, sopt->sopt_dir,
2009 				    sopt->sopt_name);
2010 			}
2011 #endif
2012 			INP_WUNLOCK(inp);
2013 			break;
2014 
2015 		case TCP_NOPUSH:
2016 			INP_WUNLOCK(inp);
2017 			error = sooptcopyin(sopt, &optval, sizeof optval,
2018 			    sizeof optval);
2019 			if (error)
2020 				return (error);
2021 
2022 			INP_WLOCK_RECHECK(inp);
2023 			if (optval)
2024 				tp->t_flags |= TF_NOPUSH;
2025 			else if (tp->t_flags & TF_NOPUSH) {
2026 				tp->t_flags &= ~TF_NOPUSH;
2027 				if (TCPS_HAVEESTABLISHED(tp->t_state)) {
2028 					struct epoch_tracker et;
2029 
2030 					NET_EPOCH_ENTER(et);
2031 					error = tp->t_fb->tfb_tcp_output(tp);
2032 					NET_EPOCH_EXIT(et);
2033 				}
2034 			}
2035 			goto unlock_and_done;
2036 
2037 		case TCP_REMOTE_UDP_ENCAPS_PORT:
2038 			INP_WUNLOCK(inp);
2039 			error = sooptcopyin(sopt, &optval, sizeof optval,
2040 			    sizeof optval);
2041 			if (error)
2042 				return (error);
2043 			if ((optval < TCP_TUNNELING_PORT_MIN) ||
2044 			    (optval > TCP_TUNNELING_PORT_MAX)) {
2045 				/* Its got to be in range */
2046 				return (EINVAL);
2047 			}
2048 			if ((V_tcp_udp_tunneling_port == 0) && (optval != 0)) {
2049 				/* You have to have enabled a UDP tunneling port first */
2050 				return (EINVAL);
2051 			}
2052 			INP_WLOCK_RECHECK(inp);
2053 			if (tp->t_state != TCPS_CLOSED) {
2054 				/* You can't change after you are connected */
2055 				error = EINVAL;
2056 			} else {
2057 				/* Ok we are all good set the port */
2058 				tp->t_port = htons(optval);
2059 			}
2060 			goto unlock_and_done;
2061 
2062 		case TCP_MAXSEG:
2063 			INP_WUNLOCK(inp);
2064 			error = sooptcopyin(sopt, &optval, sizeof optval,
2065 			    sizeof optval);
2066 			if (error)
2067 				return (error);
2068 
2069 			INP_WLOCK_RECHECK(inp);
2070 			if (optval > 0 && optval <= tp->t_maxseg &&
2071 			    optval + 40 >= V_tcp_minmss)
2072 				tp->t_maxseg = optval;
2073 			else
2074 				error = EINVAL;
2075 			goto unlock_and_done;
2076 
2077 		case TCP_INFO:
2078 			INP_WUNLOCK(inp);
2079 			error = EINVAL;
2080 			break;
2081 
2082 		case TCP_STATS:
2083 			INP_WUNLOCK(inp);
2084 #ifdef STATS
2085 			error = sooptcopyin(sopt, &optval, sizeof optval,
2086 			    sizeof optval);
2087 			if (error)
2088 				return (error);
2089 
2090 			if (optval > 0)
2091 				sbp = stats_blob_alloc(
2092 				    V_tcp_perconn_stats_dflt_tpl, 0);
2093 			else
2094 				sbp = NULL;
2095 
2096 			INP_WLOCK_RECHECK(inp);
2097 			if ((tp->t_stats != NULL && sbp == NULL) ||
2098 			    (tp->t_stats == NULL && sbp != NULL)) {
2099 				struct statsblob *t = tp->t_stats;
2100 				tp->t_stats = sbp;
2101 				sbp = t;
2102 			}
2103 			INP_WUNLOCK(inp);
2104 
2105 			stats_blob_destroy(sbp);
2106 #else
2107 			return (EOPNOTSUPP);
2108 #endif /* !STATS */
2109 			break;
2110 
2111 		case TCP_CONGESTION:
2112 			INP_WUNLOCK(inp);
2113 			error = sooptcopyin(sopt, buf, TCP_CA_NAME_MAX - 1, 1);
2114 			if (error)
2115 				break;
2116 			buf[sopt->sopt_valsize] = '\0';
2117 			INP_WLOCK_RECHECK(inp);
2118 			CC_LIST_RLOCK();
2119 			STAILQ_FOREACH(algo, &cc_list, entries)
2120 				if (strncmp(buf, algo->name,
2121 				    TCP_CA_NAME_MAX) == 0)
2122 					break;
2123 			CC_LIST_RUNLOCK();
2124 			if (algo == NULL) {
2125 				INP_WUNLOCK(inp);
2126 				error = EINVAL;
2127 				break;
2128 			}
2129 			/*
2130 			 * We hold a write lock over the tcb so it's safe to
2131 			 * do these things without ordering concerns.
2132 			 */
2133 			if (CC_ALGO(tp)->cb_destroy != NULL)
2134 				CC_ALGO(tp)->cb_destroy(tp->ccv);
2135 			CC_DATA(tp) = NULL;
2136 			CC_ALGO(tp) = algo;
2137 			/*
2138 			 * If something goes pear shaped initialising the new
2139 			 * algo, fall back to newreno (which does not
2140 			 * require initialisation).
2141 			 */
2142 			if (algo->cb_init != NULL &&
2143 			    algo->cb_init(tp->ccv) != 0) {
2144 				CC_ALGO(tp) = &newreno_cc_algo;
2145 				/*
2146 				 * The only reason init should fail is
2147 				 * because of malloc.
2148 				 */
2149 				error = ENOMEM;
2150 			}
2151 			INP_WUNLOCK(inp);
2152 			break;
2153 
2154 		case TCP_REUSPORT_LB_NUMA:
2155 			INP_WUNLOCK(inp);
2156 			error = sooptcopyin(sopt, &optval, sizeof(optval),
2157 			    sizeof(optval));
2158 			INP_WLOCK_RECHECK(inp);
2159 			if (!error)
2160 				error = in_pcblbgroup_numa(inp, optval);
2161 			INP_WUNLOCK(inp);
2162 			break;
2163 
2164 #ifdef KERN_TLS
2165 		case TCP_TXTLS_ENABLE:
2166 			INP_WUNLOCK(inp);
2167 			error = copyin_tls_enable(sopt, &tls);
2168 			if (error)
2169 				break;
2170 			error = ktls_enable_tx(so, &tls);
2171 			break;
2172 		case TCP_TXTLS_MODE:
2173 			INP_WUNLOCK(inp);
2174 			error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui));
2175 			if (error)
2176 				return (error);
2177 
2178 			INP_WLOCK_RECHECK(inp);
2179 			error = ktls_set_tx_mode(so, ui);
2180 			INP_WUNLOCK(inp);
2181 			break;
2182 		case TCP_RXTLS_ENABLE:
2183 			INP_WUNLOCK(inp);
2184 			error = sooptcopyin(sopt, &tls, sizeof(tls),
2185 			    sizeof(tls));
2186 			if (error)
2187 				break;
2188 			error = ktls_enable_rx(so, &tls);
2189 			break;
2190 #endif
2191 
2192 		case TCP_KEEPIDLE:
2193 		case TCP_KEEPINTVL:
2194 		case TCP_KEEPINIT:
2195 			INP_WUNLOCK(inp);
2196 			error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui));
2197 			if (error)
2198 				return (error);
2199 
2200 			if (ui > (UINT_MAX / hz)) {
2201 				error = EINVAL;
2202 				break;
2203 			}
2204 			ui *= hz;
2205 
2206 			INP_WLOCK_RECHECK(inp);
2207 			switch (sopt->sopt_name) {
2208 			case TCP_KEEPIDLE:
2209 				tp->t_keepidle = ui;
2210 				/*
2211 				 * XXX: better check current remaining
2212 				 * timeout and "merge" it with new value.
2213 				 */
2214 				if ((tp->t_state > TCPS_LISTEN) &&
2215 				    (tp->t_state <= TCPS_CLOSING))
2216 					tcp_timer_activate(tp, TT_KEEP,
2217 					    TP_KEEPIDLE(tp));
2218 				break;
2219 			case TCP_KEEPINTVL:
2220 				tp->t_keepintvl = ui;
2221 				if ((tp->t_state == TCPS_FIN_WAIT_2) &&
2222 				    (TP_MAXIDLE(tp) > 0))
2223 					tcp_timer_activate(tp, TT_2MSL,
2224 					    TP_MAXIDLE(tp));
2225 				break;
2226 			case TCP_KEEPINIT:
2227 				tp->t_keepinit = ui;
2228 				if (tp->t_state == TCPS_SYN_RECEIVED ||
2229 				    tp->t_state == TCPS_SYN_SENT)
2230 					tcp_timer_activate(tp, TT_KEEP,
2231 					    TP_KEEPINIT(tp));
2232 				break;
2233 			}
2234 			goto unlock_and_done;
2235 
2236 		case TCP_KEEPCNT:
2237 			INP_WUNLOCK(inp);
2238 			error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui));
2239 			if (error)
2240 				return (error);
2241 
2242 			INP_WLOCK_RECHECK(inp);
2243 			tp->t_keepcnt = ui;
2244 			if ((tp->t_state == TCPS_FIN_WAIT_2) &&
2245 			    (TP_MAXIDLE(tp) > 0))
2246 				tcp_timer_activate(tp, TT_2MSL,
2247 				    TP_MAXIDLE(tp));
2248 			goto unlock_and_done;
2249 
2250 #ifdef TCPPCAP
2251 		case TCP_PCAP_OUT:
2252 		case TCP_PCAP_IN:
2253 			INP_WUNLOCK(inp);
2254 			error = sooptcopyin(sopt, &optval, sizeof optval,
2255 			    sizeof optval);
2256 			if (error)
2257 				return (error);
2258 
2259 			INP_WLOCK_RECHECK(inp);
2260 			if (optval >= 0)
2261 				tcp_pcap_set_sock_max(TCP_PCAP_OUT ?
2262 					&(tp->t_outpkts) : &(tp->t_inpkts),
2263 					optval);
2264 			else
2265 				error = EINVAL;
2266 			goto unlock_and_done;
2267 #endif
2268 
2269 		case TCP_FASTOPEN: {
2270 			struct tcp_fastopen tfo_optval;
2271 
2272 			INP_WUNLOCK(inp);
2273 			if (!V_tcp_fastopen_client_enable &&
2274 			    !V_tcp_fastopen_server_enable)
2275 				return (EPERM);
2276 
2277 			error = sooptcopyin(sopt, &tfo_optval,
2278 				    sizeof(tfo_optval), sizeof(int));
2279 			if (error)
2280 				return (error);
2281 
2282 			INP_WLOCK_RECHECK(inp);
2283 			if ((tp->t_state != TCPS_CLOSED) &&
2284 			    (tp->t_state != TCPS_LISTEN)) {
2285 				error = EINVAL;
2286 				goto unlock_and_done;
2287 			}
2288 			if (tfo_optval.enable) {
2289 				if (tp->t_state == TCPS_LISTEN) {
2290 					if (!V_tcp_fastopen_server_enable) {
2291 						error = EPERM;
2292 						goto unlock_and_done;
2293 					}
2294 
2295 					if (tp->t_tfo_pending == NULL)
2296 						tp->t_tfo_pending =
2297 						    tcp_fastopen_alloc_counter();
2298 				} else {
2299 					/*
2300 					 * If a pre-shared key was provided,
2301 					 * stash it in the client cookie
2302 					 * field of the tcpcb for use during
2303 					 * connect.
2304 					 */
2305 					if (sopt->sopt_valsize ==
2306 					    sizeof(tfo_optval)) {
2307 						memcpy(tp->t_tfo_cookie.client,
2308 						       tfo_optval.psk,
2309 						       TCP_FASTOPEN_PSK_LEN);
2310 						tp->t_tfo_client_cookie_len =
2311 						    TCP_FASTOPEN_PSK_LEN;
2312 					}
2313 				}
2314 				tp->t_flags |= TF_FASTOPEN;
2315 			} else
2316 				tp->t_flags &= ~TF_FASTOPEN;
2317 			goto unlock_and_done;
2318 		}
2319 
2320 #ifdef TCP_BLACKBOX
2321 		case TCP_LOG:
2322 			INP_WUNLOCK(inp);
2323 			error = sooptcopyin(sopt, &optval, sizeof optval,
2324 			    sizeof optval);
2325 			if (error)
2326 				return (error);
2327 
2328 			INP_WLOCK_RECHECK(inp);
2329 			error = tcp_log_state_change(tp, optval);
2330 			goto unlock_and_done;
2331 
2332 		case TCP_LOGBUF:
2333 			INP_WUNLOCK(inp);
2334 			error = EINVAL;
2335 			break;
2336 
2337 		case TCP_LOGID:
2338 			INP_WUNLOCK(inp);
2339 			error = sooptcopyin(sopt, buf, TCP_LOG_ID_LEN - 1, 0);
2340 			if (error)
2341 				break;
2342 			buf[sopt->sopt_valsize] = '\0';
2343 			INP_WLOCK_RECHECK(inp);
2344 			error = tcp_log_set_id(tp, buf);
2345 			/* tcp_log_set_id() unlocks the INP. */
2346 			break;
2347 
2348 		case TCP_LOGDUMP:
2349 		case TCP_LOGDUMPID:
2350 			INP_WUNLOCK(inp);
2351 			error =
2352 			    sooptcopyin(sopt, buf, TCP_LOG_REASON_LEN - 1, 0);
2353 			if (error)
2354 				break;
2355 			buf[sopt->sopt_valsize] = '\0';
2356 			INP_WLOCK_RECHECK(inp);
2357 			if (sopt->sopt_name == TCP_LOGDUMP) {
2358 				error = tcp_log_dump_tp_logbuf(tp, buf,
2359 				    M_WAITOK, true);
2360 				INP_WUNLOCK(inp);
2361 			} else {
2362 				tcp_log_dump_tp_bucket_logbufs(tp, buf);
2363 				/*
2364 				 * tcp_log_dump_tp_bucket_logbufs() drops the
2365 				 * INP lock.
2366 				 */
2367 			}
2368 			break;
2369 #endif
2370 
2371 		default:
2372 			INP_WUNLOCK(inp);
2373 			error = ENOPROTOOPT;
2374 			break;
2375 		}
2376 		break;
2377 
2378 	case SOPT_GET:
2379 		tp = intotcpcb(inp);
2380 		switch (sopt->sopt_name) {
2381 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
2382 		case TCP_MD5SIG:
2383 			if (!TCPMD5_ENABLED()) {
2384 				INP_WUNLOCK(inp);
2385 				return (ENOPROTOOPT);
2386 			}
2387 			error = TCPMD5_PCBCTL(inp, sopt);
2388 			break;
2389 #endif
2390 
2391 		case TCP_NODELAY:
2392 			optval = tp->t_flags & TF_NODELAY;
2393 			INP_WUNLOCK(inp);
2394 			error = sooptcopyout(sopt, &optval, sizeof optval);
2395 			break;
2396 		case TCP_MAXSEG:
2397 			optval = tp->t_maxseg;
2398 			INP_WUNLOCK(inp);
2399 			error = sooptcopyout(sopt, &optval, sizeof optval);
2400 			break;
2401 		case TCP_REMOTE_UDP_ENCAPS_PORT:
2402 			optval = ntohs(tp->t_port);
2403 			INP_WUNLOCK(inp);
2404 			error = sooptcopyout(sopt, &optval, sizeof optval);
2405 			break;
2406 		case TCP_NOOPT:
2407 			optval = tp->t_flags & TF_NOOPT;
2408 			INP_WUNLOCK(inp);
2409 			error = sooptcopyout(sopt, &optval, sizeof optval);
2410 			break;
2411 		case TCP_NOPUSH:
2412 			optval = tp->t_flags & TF_NOPUSH;
2413 			INP_WUNLOCK(inp);
2414 			error = sooptcopyout(sopt, &optval, sizeof optval);
2415 			break;
2416 		case TCP_INFO:
2417 			tcp_fill_info(tp, &ti);
2418 			INP_WUNLOCK(inp);
2419 			error = sooptcopyout(sopt, &ti, sizeof ti);
2420 			break;
2421 		case TCP_STATS:
2422 			{
2423 #ifdef STATS
2424 			int nheld;
2425 			TYPEOF_MEMBER(struct statsblob, flags) sbflags = 0;
2426 
2427 			error = 0;
2428 			socklen_t outsbsz = sopt->sopt_valsize;
2429 			if (tp->t_stats == NULL)
2430 				error = ENOENT;
2431 			else if (outsbsz >= tp->t_stats->cursz)
2432 				outsbsz = tp->t_stats->cursz;
2433 			else if (outsbsz >= sizeof(struct statsblob))
2434 				outsbsz = sizeof(struct statsblob);
2435 			else
2436 				error = EINVAL;
2437 			INP_WUNLOCK(inp);
2438 			if (error)
2439 				break;
2440 
2441 			sbp = sopt->sopt_val;
2442 			nheld = atop(round_page(((vm_offset_t)sbp) +
2443 			    (vm_size_t)outsbsz) - trunc_page((vm_offset_t)sbp));
2444 			vm_page_t ma[nheld];
2445 			if (vm_fault_quick_hold_pages(
2446 			    &curproc->p_vmspace->vm_map, (vm_offset_t)sbp,
2447 			    outsbsz, VM_PROT_READ | VM_PROT_WRITE, ma,
2448 			    nheld) < 0) {
2449 				error = EFAULT;
2450 				break;
2451 			}
2452 
2453 			if ((error = copyin_nofault(&(sbp->flags), &sbflags,
2454 			    SIZEOF_MEMBER(struct statsblob, flags))))
2455 				goto unhold;
2456 
2457 			INP_WLOCK_RECHECK(inp);
2458 			error = stats_blob_snapshot(&sbp, outsbsz, tp->t_stats,
2459 			    sbflags | SB_CLONE_USRDSTNOFAULT);
2460 			INP_WUNLOCK(inp);
2461 			sopt->sopt_valsize = outsbsz;
2462 unhold:
2463 			vm_page_unhold_pages(ma, nheld);
2464 #else
2465 			INP_WUNLOCK(inp);
2466 			error = EOPNOTSUPP;
2467 #endif /* !STATS */
2468 			break;
2469 			}
2470 		case TCP_CONGESTION:
2471 			len = strlcpy(buf, CC_ALGO(tp)->name, TCP_CA_NAME_MAX);
2472 			INP_WUNLOCK(inp);
2473 			error = sooptcopyout(sopt, buf, len + 1);
2474 			break;
2475 		case TCP_KEEPIDLE:
2476 		case TCP_KEEPINTVL:
2477 		case TCP_KEEPINIT:
2478 		case TCP_KEEPCNT:
2479 			switch (sopt->sopt_name) {
2480 			case TCP_KEEPIDLE:
2481 				ui = TP_KEEPIDLE(tp) / hz;
2482 				break;
2483 			case TCP_KEEPINTVL:
2484 				ui = TP_KEEPINTVL(tp) / hz;
2485 				break;
2486 			case TCP_KEEPINIT:
2487 				ui = TP_KEEPINIT(tp) / hz;
2488 				break;
2489 			case TCP_KEEPCNT:
2490 				ui = TP_KEEPCNT(tp);
2491 				break;
2492 			}
2493 			INP_WUNLOCK(inp);
2494 			error = sooptcopyout(sopt, &ui, sizeof(ui));
2495 			break;
2496 #ifdef TCPPCAP
2497 		case TCP_PCAP_OUT:
2498 		case TCP_PCAP_IN:
2499 			optval = tcp_pcap_get_sock_max(TCP_PCAP_OUT ?
2500 					&(tp->t_outpkts) : &(tp->t_inpkts));
2501 			INP_WUNLOCK(inp);
2502 			error = sooptcopyout(sopt, &optval, sizeof optval);
2503 			break;
2504 #endif
2505 		case TCP_FASTOPEN:
2506 			optval = tp->t_flags & TF_FASTOPEN;
2507 			INP_WUNLOCK(inp);
2508 			error = sooptcopyout(sopt, &optval, sizeof optval);
2509 			break;
2510 #ifdef TCP_BLACKBOX
2511 		case TCP_LOG:
2512 			optval = tp->t_logstate;
2513 			INP_WUNLOCK(inp);
2514 			error = sooptcopyout(sopt, &optval, sizeof(optval));
2515 			break;
2516 		case TCP_LOGBUF:
2517 			/* tcp_log_getlogbuf() does INP_WUNLOCK(inp) */
2518 			error = tcp_log_getlogbuf(sopt, tp);
2519 			break;
2520 		case TCP_LOGID:
2521 			len = tcp_log_get_id(tp, buf);
2522 			INP_WUNLOCK(inp);
2523 			error = sooptcopyout(sopt, buf, len + 1);
2524 			break;
2525 		case TCP_LOGDUMP:
2526 		case TCP_LOGDUMPID:
2527 			INP_WUNLOCK(inp);
2528 			error = EINVAL;
2529 			break;
2530 #endif
2531 #ifdef KERN_TLS
2532 		case TCP_TXTLS_MODE:
2533 			optval = ktls_get_tx_mode(so);
2534 			INP_WUNLOCK(inp);
2535 			error = sooptcopyout(sopt, &optval, sizeof(optval));
2536 			break;
2537 		case TCP_RXTLS_MODE:
2538 			optval = ktls_get_rx_mode(so);
2539 			INP_WUNLOCK(inp);
2540 			error = sooptcopyout(sopt, &optval, sizeof(optval));
2541 			break;
2542 #endif
2543 		default:
2544 			INP_WUNLOCK(inp);
2545 			error = ENOPROTOOPT;
2546 			break;
2547 		}
2548 		break;
2549 	}
2550 	return (error);
2551 }
2552 #undef INP_WLOCK_RECHECK
2553 #undef INP_WLOCK_RECHECK_CLEANUP
2554 
2555 /*
2556  * Initiate (or continue) disconnect.
2557  * If embryonic state, just send reset (once).
2558  * If in ``let data drain'' option and linger null, just drop.
2559  * Otherwise (hard), mark socket disconnecting and drop
2560  * current input data; switch states based on user close, and
2561  * send segment to peer (with FIN).
2562  */
2563 static void
2564 tcp_disconnect(struct tcpcb *tp)
2565 {
2566 	struct inpcb *inp = tp->t_inpcb;
2567 	struct socket *so = inp->inp_socket;
2568 
2569 	NET_EPOCH_ASSERT();
2570 	INP_WLOCK_ASSERT(inp);
2571 
2572 	/*
2573 	 * Neither tcp_close() nor tcp_drop() should return NULL, as the
2574 	 * socket is still open.
2575 	 */
2576 	if (tp->t_state < TCPS_ESTABLISHED &&
2577 	    !(tp->t_state > TCPS_LISTEN && IS_FASTOPEN(tp->t_flags))) {
2578 		tp = tcp_close(tp);
2579 		KASSERT(tp != NULL,
2580 		    ("tcp_disconnect: tcp_close() returned NULL"));
2581 	} else if ((so->so_options & SO_LINGER) && so->so_linger == 0) {
2582 		tp = tcp_drop(tp, 0);
2583 		KASSERT(tp != NULL,
2584 		    ("tcp_disconnect: tcp_drop() returned NULL"));
2585 	} else {
2586 		soisdisconnecting(so);
2587 		sbflush(&so->so_rcv);
2588 		tcp_usrclosed(tp);
2589 		if (!(inp->inp_flags & INP_DROPPED))
2590 			tp->t_fb->tfb_tcp_output(tp);
2591 	}
2592 }
2593 
2594 /*
2595  * User issued close, and wish to trail through shutdown states:
2596  * if never received SYN, just forget it.  If got a SYN from peer,
2597  * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
2598  * If already got a FIN from peer, then almost done; go to LAST_ACK
2599  * state.  In all other cases, have already sent FIN to peer (e.g.
2600  * after PRU_SHUTDOWN), and just have to play tedious game waiting
2601  * for peer to send FIN or not respond to keep-alives, etc.
2602  * We can let the user exit from the close as soon as the FIN is acked.
2603  */
2604 static void
2605 tcp_usrclosed(struct tcpcb *tp)
2606 {
2607 
2608 	NET_EPOCH_ASSERT();
2609 	INP_WLOCK_ASSERT(tp->t_inpcb);
2610 
2611 	switch (tp->t_state) {
2612 	case TCPS_LISTEN:
2613 #ifdef TCP_OFFLOAD
2614 		tcp_offload_listen_stop(tp);
2615 #endif
2616 		tcp_state_change(tp, TCPS_CLOSED);
2617 		/* FALLTHROUGH */
2618 	case TCPS_CLOSED:
2619 		tp = tcp_close(tp);
2620 		/*
2621 		 * tcp_close() should never return NULL here as the socket is
2622 		 * still open.
2623 		 */
2624 		KASSERT(tp != NULL,
2625 		    ("tcp_usrclosed: tcp_close() returned NULL"));
2626 		break;
2627 
2628 	case TCPS_SYN_SENT:
2629 	case TCPS_SYN_RECEIVED:
2630 		tp->t_flags |= TF_NEEDFIN;
2631 		break;
2632 
2633 	case TCPS_ESTABLISHED:
2634 		tcp_state_change(tp, TCPS_FIN_WAIT_1);
2635 		break;
2636 
2637 	case TCPS_CLOSE_WAIT:
2638 		tcp_state_change(tp, TCPS_LAST_ACK);
2639 		break;
2640 	}
2641 	if (tp->t_state >= TCPS_FIN_WAIT_2) {
2642 		soisdisconnected(tp->t_inpcb->inp_socket);
2643 		/* Prevent the connection hanging in FIN_WAIT_2 forever. */
2644 		if (tp->t_state == TCPS_FIN_WAIT_2) {
2645 			int timeout;
2646 
2647 			timeout = (tcp_fast_finwait2_recycle) ?
2648 			    tcp_finwait2_timeout : TP_MAXIDLE(tp);
2649 			tcp_timer_activate(tp, TT_2MSL, timeout);
2650 		}
2651 	}
2652 }
2653 
2654 #ifdef DDB
2655 static void
2656 db_print_indent(int indent)
2657 {
2658 	int i;
2659 
2660 	for (i = 0; i < indent; i++)
2661 		db_printf(" ");
2662 }
2663 
2664 static void
2665 db_print_tstate(int t_state)
2666 {
2667 
2668 	switch (t_state) {
2669 	case TCPS_CLOSED:
2670 		db_printf("TCPS_CLOSED");
2671 		return;
2672 
2673 	case TCPS_LISTEN:
2674 		db_printf("TCPS_LISTEN");
2675 		return;
2676 
2677 	case TCPS_SYN_SENT:
2678 		db_printf("TCPS_SYN_SENT");
2679 		return;
2680 
2681 	case TCPS_SYN_RECEIVED:
2682 		db_printf("TCPS_SYN_RECEIVED");
2683 		return;
2684 
2685 	case TCPS_ESTABLISHED:
2686 		db_printf("TCPS_ESTABLISHED");
2687 		return;
2688 
2689 	case TCPS_CLOSE_WAIT:
2690 		db_printf("TCPS_CLOSE_WAIT");
2691 		return;
2692 
2693 	case TCPS_FIN_WAIT_1:
2694 		db_printf("TCPS_FIN_WAIT_1");
2695 		return;
2696 
2697 	case TCPS_CLOSING:
2698 		db_printf("TCPS_CLOSING");
2699 		return;
2700 
2701 	case TCPS_LAST_ACK:
2702 		db_printf("TCPS_LAST_ACK");
2703 		return;
2704 
2705 	case TCPS_FIN_WAIT_2:
2706 		db_printf("TCPS_FIN_WAIT_2");
2707 		return;
2708 
2709 	case TCPS_TIME_WAIT:
2710 		db_printf("TCPS_TIME_WAIT");
2711 		return;
2712 
2713 	default:
2714 		db_printf("unknown");
2715 		return;
2716 	}
2717 }
2718 
2719 static void
2720 db_print_tflags(u_int t_flags)
2721 {
2722 	int comma;
2723 
2724 	comma = 0;
2725 	if (t_flags & TF_ACKNOW) {
2726 		db_printf("%sTF_ACKNOW", comma ? ", " : "");
2727 		comma = 1;
2728 	}
2729 	if (t_flags & TF_DELACK) {
2730 		db_printf("%sTF_DELACK", comma ? ", " : "");
2731 		comma = 1;
2732 	}
2733 	if (t_flags & TF_NODELAY) {
2734 		db_printf("%sTF_NODELAY", comma ? ", " : "");
2735 		comma = 1;
2736 	}
2737 	if (t_flags & TF_NOOPT) {
2738 		db_printf("%sTF_NOOPT", comma ? ", " : "");
2739 		comma = 1;
2740 	}
2741 	if (t_flags & TF_SENTFIN) {
2742 		db_printf("%sTF_SENTFIN", comma ? ", " : "");
2743 		comma = 1;
2744 	}
2745 	if (t_flags & TF_REQ_SCALE) {
2746 		db_printf("%sTF_REQ_SCALE", comma ? ", " : "");
2747 		comma = 1;
2748 	}
2749 	if (t_flags & TF_RCVD_SCALE) {
2750 		db_printf("%sTF_RECVD_SCALE", comma ? ", " : "");
2751 		comma = 1;
2752 	}
2753 	if (t_flags & TF_REQ_TSTMP) {
2754 		db_printf("%sTF_REQ_TSTMP", comma ? ", " : "");
2755 		comma = 1;
2756 	}
2757 	if (t_flags & TF_RCVD_TSTMP) {
2758 		db_printf("%sTF_RCVD_TSTMP", comma ? ", " : "");
2759 		comma = 1;
2760 	}
2761 	if (t_flags & TF_SACK_PERMIT) {
2762 		db_printf("%sTF_SACK_PERMIT", comma ? ", " : "");
2763 		comma = 1;
2764 	}
2765 	if (t_flags & TF_NEEDSYN) {
2766 		db_printf("%sTF_NEEDSYN", comma ? ", " : "");
2767 		comma = 1;
2768 	}
2769 	if (t_flags & TF_NEEDFIN) {
2770 		db_printf("%sTF_NEEDFIN", comma ? ", " : "");
2771 		comma = 1;
2772 	}
2773 	if (t_flags & TF_NOPUSH) {
2774 		db_printf("%sTF_NOPUSH", comma ? ", " : "");
2775 		comma = 1;
2776 	}
2777 	if (t_flags & TF_MORETOCOME) {
2778 		db_printf("%sTF_MORETOCOME", comma ? ", " : "");
2779 		comma = 1;
2780 	}
2781 	if (t_flags & TF_LQ_OVERFLOW) {
2782 		db_printf("%sTF_LQ_OVERFLOW", comma ? ", " : "");
2783 		comma = 1;
2784 	}
2785 	if (t_flags & TF_LASTIDLE) {
2786 		db_printf("%sTF_LASTIDLE", comma ? ", " : "");
2787 		comma = 1;
2788 	}
2789 	if (t_flags & TF_RXWIN0SENT) {
2790 		db_printf("%sTF_RXWIN0SENT", comma ? ", " : "");
2791 		comma = 1;
2792 	}
2793 	if (t_flags & TF_FASTRECOVERY) {
2794 		db_printf("%sTF_FASTRECOVERY", comma ? ", " : "");
2795 		comma = 1;
2796 	}
2797 	if (t_flags & TF_CONGRECOVERY) {
2798 		db_printf("%sTF_CONGRECOVERY", comma ? ", " : "");
2799 		comma = 1;
2800 	}
2801 	if (t_flags & TF_WASFRECOVERY) {
2802 		db_printf("%sTF_WASFRECOVERY", comma ? ", " : "");
2803 		comma = 1;
2804 	}
2805 	if (t_flags & TF_SIGNATURE) {
2806 		db_printf("%sTF_SIGNATURE", comma ? ", " : "");
2807 		comma = 1;
2808 	}
2809 	if (t_flags & TF_FORCEDATA) {
2810 		db_printf("%sTF_FORCEDATA", comma ? ", " : "");
2811 		comma = 1;
2812 	}
2813 	if (t_flags & TF_TSO) {
2814 		db_printf("%sTF_TSO", comma ? ", " : "");
2815 		comma = 1;
2816 	}
2817 	if (t_flags & TF_FASTOPEN) {
2818 		db_printf("%sTF_FASTOPEN", comma ? ", " : "");
2819 		comma = 1;
2820 	}
2821 }
2822 
2823 static void
2824 db_print_tflags2(u_int t_flags2)
2825 {
2826 	int comma;
2827 
2828 	comma = 0;
2829 	if (t_flags2 & TF2_ECN_PERMIT) {
2830 		db_printf("%sTF2_ECN_PERMIT", comma ? ", " : "");
2831 		comma = 1;
2832 	}
2833 }
2834 
2835 static void
2836 db_print_toobflags(char t_oobflags)
2837 {
2838 	int comma;
2839 
2840 	comma = 0;
2841 	if (t_oobflags & TCPOOB_HAVEDATA) {
2842 		db_printf("%sTCPOOB_HAVEDATA", comma ? ", " : "");
2843 		comma = 1;
2844 	}
2845 	if (t_oobflags & TCPOOB_HADDATA) {
2846 		db_printf("%sTCPOOB_HADDATA", comma ? ", " : "");
2847 		comma = 1;
2848 	}
2849 }
2850 
2851 static void
2852 db_print_tcpcb(struct tcpcb *tp, const char *name, int indent)
2853 {
2854 
2855 	db_print_indent(indent);
2856 	db_printf("%s at %p\n", name, tp);
2857 
2858 	indent += 2;
2859 
2860 	db_print_indent(indent);
2861 	db_printf("t_segq first: %p   t_segqlen: %d   t_dupacks: %d\n",
2862 	   TAILQ_FIRST(&tp->t_segq), tp->t_segqlen, tp->t_dupacks);
2863 
2864 	db_print_indent(indent);
2865 	db_printf("tt_rexmt: %p   tt_persist: %p   tt_keep: %p\n",
2866 	    &tp->t_timers->tt_rexmt, &tp->t_timers->tt_persist, &tp->t_timers->tt_keep);
2867 
2868 	db_print_indent(indent);
2869 	db_printf("tt_2msl: %p   tt_delack: %p   t_inpcb: %p\n", &tp->t_timers->tt_2msl,
2870 	    &tp->t_timers->tt_delack, tp->t_inpcb);
2871 
2872 	db_print_indent(indent);
2873 	db_printf("t_state: %d (", tp->t_state);
2874 	db_print_tstate(tp->t_state);
2875 	db_printf(")\n");
2876 
2877 	db_print_indent(indent);
2878 	db_printf("t_flags: 0x%x (", tp->t_flags);
2879 	db_print_tflags(tp->t_flags);
2880 	db_printf(")\n");
2881 
2882 	db_print_indent(indent);
2883 	db_printf("t_flags2: 0x%x (", tp->t_flags2);
2884 	db_print_tflags2(tp->t_flags2);
2885 	db_printf(")\n");
2886 
2887 	db_print_indent(indent);
2888 	db_printf("snd_una: 0x%08x   snd_max: 0x%08x   snd_nxt: x0%08x\n",
2889 	    tp->snd_una, tp->snd_max, tp->snd_nxt);
2890 
2891 	db_print_indent(indent);
2892 	db_printf("snd_up: 0x%08x   snd_wl1: 0x%08x   snd_wl2: 0x%08x\n",
2893 	   tp->snd_up, tp->snd_wl1, tp->snd_wl2);
2894 
2895 	db_print_indent(indent);
2896 	db_printf("iss: 0x%08x   irs: 0x%08x   rcv_nxt: 0x%08x\n",
2897 	    tp->iss, tp->irs, tp->rcv_nxt);
2898 
2899 	db_print_indent(indent);
2900 	db_printf("rcv_adv: 0x%08x   rcv_wnd: %u   rcv_up: 0x%08x\n",
2901 	    tp->rcv_adv, tp->rcv_wnd, tp->rcv_up);
2902 
2903 	db_print_indent(indent);
2904 	db_printf("snd_wnd: %u   snd_cwnd: %u\n",
2905 	   tp->snd_wnd, tp->snd_cwnd);
2906 
2907 	db_print_indent(indent);
2908 	db_printf("snd_ssthresh: %u   snd_recover: "
2909 	    "0x%08x\n", tp->snd_ssthresh, tp->snd_recover);
2910 
2911 	db_print_indent(indent);
2912 	db_printf("t_rcvtime: %u   t_startime: %u\n",
2913 	    tp->t_rcvtime, tp->t_starttime);
2914 
2915 	db_print_indent(indent);
2916 	db_printf("t_rttime: %u   t_rtsq: 0x%08x\n",
2917 	    tp->t_rtttime, tp->t_rtseq);
2918 
2919 	db_print_indent(indent);
2920 	db_printf("t_rxtcur: %d   t_maxseg: %u   t_srtt: %d\n",
2921 	    tp->t_rxtcur, tp->t_maxseg, tp->t_srtt);
2922 
2923 	db_print_indent(indent);
2924 	db_printf("t_rttvar: %d   t_rxtshift: %d   t_rttmin: %u   "
2925 	    "t_rttbest: %u\n", tp->t_rttvar, tp->t_rxtshift, tp->t_rttmin,
2926 	    tp->t_rttbest);
2927 
2928 	db_print_indent(indent);
2929 	db_printf("t_rttupdated: %lu   max_sndwnd: %u   t_softerror: %d\n",
2930 	    tp->t_rttupdated, tp->max_sndwnd, tp->t_softerror);
2931 
2932 	db_print_indent(indent);
2933 	db_printf("t_oobflags: 0x%x (", tp->t_oobflags);
2934 	db_print_toobflags(tp->t_oobflags);
2935 	db_printf(")   t_iobc: 0x%02x\n", tp->t_iobc);
2936 
2937 	db_print_indent(indent);
2938 	db_printf("snd_scale: %u   rcv_scale: %u   request_r_scale: %u\n",
2939 	    tp->snd_scale, tp->rcv_scale, tp->request_r_scale);
2940 
2941 	db_print_indent(indent);
2942 	db_printf("ts_recent: %u   ts_recent_age: %u\n",
2943 	    tp->ts_recent, tp->ts_recent_age);
2944 
2945 	db_print_indent(indent);
2946 	db_printf("ts_offset: %u   last_ack_sent: 0x%08x   snd_cwnd_prev: "
2947 	    "%u\n", tp->ts_offset, tp->last_ack_sent, tp->snd_cwnd_prev);
2948 
2949 	db_print_indent(indent);
2950 	db_printf("snd_ssthresh_prev: %u   snd_recover_prev: 0x%08x   "
2951 	    "t_badrxtwin: %u\n", tp->snd_ssthresh_prev,
2952 	    tp->snd_recover_prev, tp->t_badrxtwin);
2953 
2954 	db_print_indent(indent);
2955 	db_printf("snd_numholes: %d  snd_holes first: %p\n",
2956 	    tp->snd_numholes, TAILQ_FIRST(&tp->snd_holes));
2957 
2958 	db_print_indent(indent);
2959 	db_printf("snd_fack: 0x%08x   rcv_numsacks: %d\n",
2960 	    tp->snd_fack, tp->rcv_numsacks);
2961 
2962 	/* Skip sackblks, sackhint. */
2963 
2964 	db_print_indent(indent);
2965 	db_printf("t_rttlow: %d   rfbuf_ts: %u   rfbuf_cnt: %d\n",
2966 	    tp->t_rttlow, tp->rfbuf_ts, tp->rfbuf_cnt);
2967 }
2968 
2969 DB_SHOW_COMMAND(tcpcb, db_show_tcpcb)
2970 {
2971 	struct tcpcb *tp;
2972 
2973 	if (!have_addr) {
2974 		db_printf("usage: show tcpcb <addr>\n");
2975 		return;
2976 	}
2977 	tp = (struct tcpcb *)addr;
2978 
2979 	db_print_tcpcb(tp, "tcpcb", 0);
2980 }
2981 #endif
2982