xref: /freebsd/sys/netinet/tcp_usrreq.c (revision dcf58f92e2c19a32fc171f763698e711c719badc)
1 /*-
2  * Copyright (c) 1982, 1986, 1988, 1993
3  *	The Regents of the University of California.
4  * Copyright (c) 2006-2007 Robert N. M. Watson
5  * Copyright (c) 2010-2011 Juniper Networks, Inc.
6  * All rights reserved.
7  *
8  * Portions of this software were developed by Robert N. M. Watson under
9  * contract to Juniper Networks, Inc.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	From: @(#)tcp_usrreq.c	8.2 (Berkeley) 1/3/94
36  */
37 
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40 
41 #include "opt_ddb.h"
42 #include "opt_inet.h"
43 #include "opt_inet6.h"
44 #include "opt_tcpdebug.h"
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/limits.h>
49 #include <sys/malloc.h>
50 #include <sys/kernel.h>
51 #include <sys/sysctl.h>
52 #include <sys/mbuf.h>
53 #ifdef INET6
54 #include <sys/domain.h>
55 #endif /* INET6 */
56 #include <sys/socket.h>
57 #include <sys/socketvar.h>
58 #include <sys/protosw.h>
59 #include <sys/proc.h>
60 #include <sys/jail.h>
61 
62 #ifdef DDB
63 #include <ddb/ddb.h>
64 #endif
65 
66 #include <net/if.h>
67 #include <net/if_var.h>
68 #include <net/route.h>
69 #include <net/vnet.h>
70 
71 #include <netinet/cc.h>
72 #include <netinet/in.h>
73 #include <netinet/in_pcb.h>
74 #include <netinet/in_systm.h>
75 #include <netinet/in_var.h>
76 #include <netinet/ip_var.h>
77 #ifdef INET6
78 #include <netinet/ip6.h>
79 #include <netinet6/in6_pcb.h>
80 #include <netinet6/ip6_var.h>
81 #include <netinet6/scope6_var.h>
82 #endif
83 #include <netinet/tcp_fsm.h>
84 #include <netinet/tcp_seq.h>
85 #include <netinet/tcp_timer.h>
86 #include <netinet/tcp_var.h>
87 #include <netinet/tcpip.h>
88 #ifdef TCPDEBUG
89 #include <netinet/tcp_debug.h>
90 #endif
91 #ifdef TCP_OFFLOAD
92 #include <netinet/tcp_offload.h>
93 #endif
94 
95 /*
96  * TCP protocol interface to socket abstraction.
97  */
98 static int	tcp_attach(struct socket *);
99 #ifdef INET
100 static int	tcp_connect(struct tcpcb *, struct sockaddr *,
101 		    struct thread *td);
102 #endif /* INET */
103 #ifdef INET6
104 static int	tcp6_connect(struct tcpcb *, struct sockaddr *,
105 		    struct thread *td);
106 #endif /* INET6 */
107 static void	tcp_disconnect(struct tcpcb *);
108 static void	tcp_usrclosed(struct tcpcb *);
109 static void	tcp_fill_info(struct tcpcb *, struct tcp_info *);
110 
111 #ifdef TCPDEBUG
112 #define	TCPDEBUG0	int ostate = 0
113 #define	TCPDEBUG1()	ostate = tp ? tp->t_state : 0
114 #define	TCPDEBUG2(req)	if (tp && (so->so_options & SO_DEBUG)) \
115 				tcp_trace(TA_USER, ostate, tp, 0, 0, req)
116 #else
117 #define	TCPDEBUG0
118 #define	TCPDEBUG1()
119 #define	TCPDEBUG2(req)
120 #endif
121 
122 /*
123  * TCP attaches to socket via pru_attach(), reserving space,
124  * and an internet control block.
125  */
126 static int
127 tcp_usr_attach(struct socket *so, int proto, struct thread *td)
128 {
129 	struct inpcb *inp;
130 	struct tcpcb *tp = NULL;
131 	int error;
132 	TCPDEBUG0;
133 
134 	inp = sotoinpcb(so);
135 	KASSERT(inp == NULL, ("tcp_usr_attach: inp != NULL"));
136 	TCPDEBUG1();
137 
138 	error = tcp_attach(so);
139 	if (error)
140 		goto out;
141 
142 	if ((so->so_options & SO_LINGER) && so->so_linger == 0)
143 		so->so_linger = TCP_LINGERTIME;
144 
145 	inp = sotoinpcb(so);
146 	tp = intotcpcb(inp);
147 out:
148 	TCPDEBUG2(PRU_ATTACH);
149 	return error;
150 }
151 
152 /*
153  * tcp_detach is called when the socket layer loses its final reference
154  * to the socket, be it a file descriptor reference, a reference from TCP,
155  * etc.  At this point, there is only one case in which we will keep around
156  * inpcb state: time wait.
157  *
158  * This function can probably be re-absorbed back into tcp_usr_detach() now
159  * that there is a single detach path.
160  */
161 static void
162 tcp_detach(struct socket *so, struct inpcb *inp)
163 {
164 	struct tcpcb *tp;
165 
166 	INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
167 	INP_WLOCK_ASSERT(inp);
168 
169 	KASSERT(so->so_pcb == inp, ("tcp_detach: so_pcb != inp"));
170 	KASSERT(inp->inp_socket == so, ("tcp_detach: inp_socket != so"));
171 
172 	tp = intotcpcb(inp);
173 
174 	if (inp->inp_flags & INP_TIMEWAIT) {
175 		/*
176 		 * There are two cases to handle: one in which the time wait
177 		 * state is being discarded (INP_DROPPED), and one in which
178 		 * this connection will remain in timewait.  In the former,
179 		 * it is time to discard all state (except tcptw, which has
180 		 * already been discarded by the timewait close code, which
181 		 * should be further up the call stack somewhere).  In the
182 		 * latter case, we detach from the socket, but leave the pcb
183 		 * present until timewait ends.
184 		 *
185 		 * XXXRW: Would it be cleaner to free the tcptw here?
186 		 *
187 		 * Astute question indeed, from twtcp perspective there are
188 		 * three cases to consider:
189 		 *
190 		 * #1 tcp_detach is called at tcptw creation time by
191 		 *  tcp_twstart, then do not discard the newly created tcptw
192 		 *  and leave inpcb present until timewait ends
193 		 * #2 tcp_detach is called at timewait end (or reuse) by
194 		 *  tcp_twclose, then the tcptw has already been discarded
195 		 *  and inpcb is freed here
196 		 * #3 tcp_detach is called() after timewait ends (or reuse)
197 		 *  (e.g. by soclose), then tcptw has already been discarded
198 		 *  and inpcb is freed here
199 		 *
200 		 *  In all three cases the tcptw should not be freed here.
201 		 */
202 		if (inp->inp_flags & INP_DROPPED) {
203 			KASSERT(tp == NULL, ("tcp_detach: INP_TIMEWAIT && "
204 			    "INP_DROPPED && tp != NULL"));
205 			in_pcbdetach(inp);
206 			in_pcbfree(inp);
207 		} else {
208 			in_pcbdetach(inp);
209 			INP_WUNLOCK(inp);
210 		}
211 	} else {
212 		/*
213 		 * If the connection is not in timewait, we consider two
214 		 * two conditions: one in which no further processing is
215 		 * necessary (dropped || embryonic), and one in which TCP is
216 		 * not yet done, but no longer requires the socket, so the
217 		 * pcb will persist for the time being.
218 		 *
219 		 * XXXRW: Does the second case still occur?
220 		 */
221 		if (inp->inp_flags & INP_DROPPED ||
222 		    tp->t_state < TCPS_SYN_SENT) {
223 			tcp_discardcb(tp);
224 			in_pcbdetach(inp);
225 			in_pcbfree(inp);
226 		} else {
227 			in_pcbdetach(inp);
228 			INP_WUNLOCK(inp);
229 		}
230 	}
231 }
232 
233 /*
234  * pru_detach() detaches the TCP protocol from the socket.
235  * If the protocol state is non-embryonic, then can't
236  * do this directly: have to initiate a pru_disconnect(),
237  * which may finish later; embryonic TCB's can just
238  * be discarded here.
239  */
240 static void
241 tcp_usr_detach(struct socket *so)
242 {
243 	struct inpcb *inp;
244 
245 	inp = sotoinpcb(so);
246 	KASSERT(inp != NULL, ("tcp_usr_detach: inp == NULL"));
247 	INP_INFO_WLOCK(&V_tcbinfo);
248 	INP_WLOCK(inp);
249 	KASSERT(inp->inp_socket != NULL,
250 	    ("tcp_usr_detach: inp_socket == NULL"));
251 	tcp_detach(so, inp);
252 	INP_INFO_WUNLOCK(&V_tcbinfo);
253 }
254 
255 #ifdef INET
256 /*
257  * Give the socket an address.
258  */
259 static int
260 tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
261 {
262 	int error = 0;
263 	struct inpcb *inp;
264 	struct tcpcb *tp = NULL;
265 	struct sockaddr_in *sinp;
266 
267 	sinp = (struct sockaddr_in *)nam;
268 	if (nam->sa_len != sizeof (*sinp))
269 		return (EINVAL);
270 	/*
271 	 * Must check for multicast addresses and disallow binding
272 	 * to them.
273 	 */
274 	if (sinp->sin_family == AF_INET &&
275 	    IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
276 		return (EAFNOSUPPORT);
277 
278 	TCPDEBUG0;
279 	inp = sotoinpcb(so);
280 	KASSERT(inp != NULL, ("tcp_usr_bind: inp == NULL"));
281 	INP_WLOCK(inp);
282 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
283 		error = EINVAL;
284 		goto out;
285 	}
286 	tp = intotcpcb(inp);
287 	TCPDEBUG1();
288 	INP_HASH_WLOCK(&V_tcbinfo);
289 	error = in_pcbbind(inp, nam, td->td_ucred);
290 	INP_HASH_WUNLOCK(&V_tcbinfo);
291 out:
292 	TCPDEBUG2(PRU_BIND);
293 	INP_WUNLOCK(inp);
294 
295 	return (error);
296 }
297 #endif /* INET */
298 
299 #ifdef INET6
300 static int
301 tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
302 {
303 	int error = 0;
304 	struct inpcb *inp;
305 	struct tcpcb *tp = NULL;
306 	struct sockaddr_in6 *sin6p;
307 
308 	sin6p = (struct sockaddr_in6 *)nam;
309 	if (nam->sa_len != sizeof (*sin6p))
310 		return (EINVAL);
311 	/*
312 	 * Must check for multicast addresses and disallow binding
313 	 * to them.
314 	 */
315 	if (sin6p->sin6_family == AF_INET6 &&
316 	    IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr))
317 		return (EAFNOSUPPORT);
318 
319 	TCPDEBUG0;
320 	inp = sotoinpcb(so);
321 	KASSERT(inp != NULL, ("tcp6_usr_bind: inp == NULL"));
322 	INP_WLOCK(inp);
323 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
324 		error = EINVAL;
325 		goto out;
326 	}
327 	tp = intotcpcb(inp);
328 	TCPDEBUG1();
329 	INP_HASH_WLOCK(&V_tcbinfo);
330 	inp->inp_vflag &= ~INP_IPV4;
331 	inp->inp_vflag |= INP_IPV6;
332 #ifdef INET
333 	if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
334 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6p->sin6_addr))
335 			inp->inp_vflag |= INP_IPV4;
336 		else if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
337 			struct sockaddr_in sin;
338 
339 			in6_sin6_2_sin(&sin, sin6p);
340 			inp->inp_vflag |= INP_IPV4;
341 			inp->inp_vflag &= ~INP_IPV6;
342 			error = in_pcbbind(inp, (struct sockaddr *)&sin,
343 			    td->td_ucred);
344 			INP_HASH_WUNLOCK(&V_tcbinfo);
345 			goto out;
346 		}
347 	}
348 #endif
349 	error = in6_pcbbind(inp, nam, td->td_ucred);
350 	INP_HASH_WUNLOCK(&V_tcbinfo);
351 out:
352 	TCPDEBUG2(PRU_BIND);
353 	INP_WUNLOCK(inp);
354 	return (error);
355 }
356 #endif /* INET6 */
357 
358 #ifdef INET
359 /*
360  * Prepare to accept connections.
361  */
362 static int
363 tcp_usr_listen(struct socket *so, int backlog, struct thread *td)
364 {
365 	int error = 0;
366 	struct inpcb *inp;
367 	struct tcpcb *tp = NULL;
368 
369 	TCPDEBUG0;
370 	inp = sotoinpcb(so);
371 	KASSERT(inp != NULL, ("tcp_usr_listen: inp == NULL"));
372 	INP_WLOCK(inp);
373 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
374 		error = EINVAL;
375 		goto out;
376 	}
377 	tp = intotcpcb(inp);
378 	TCPDEBUG1();
379 	SOCK_LOCK(so);
380 	error = solisten_proto_check(so);
381 	INP_HASH_WLOCK(&V_tcbinfo);
382 	if (error == 0 && inp->inp_lport == 0)
383 		error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
384 	INP_HASH_WUNLOCK(&V_tcbinfo);
385 	if (error == 0) {
386 		tcp_state_change(tp, TCPS_LISTEN);
387 		solisten_proto(so, backlog);
388 #ifdef TCP_OFFLOAD
389 		if ((so->so_options & SO_NO_OFFLOAD) == 0)
390 			tcp_offload_listen_start(tp);
391 #endif
392 	}
393 	SOCK_UNLOCK(so);
394 
395 out:
396 	TCPDEBUG2(PRU_LISTEN);
397 	INP_WUNLOCK(inp);
398 	return (error);
399 }
400 #endif /* INET */
401 
402 #ifdef INET6
403 static int
404 tcp6_usr_listen(struct socket *so, int backlog, struct thread *td)
405 {
406 	int error = 0;
407 	struct inpcb *inp;
408 	struct tcpcb *tp = NULL;
409 
410 	TCPDEBUG0;
411 	inp = sotoinpcb(so);
412 	KASSERT(inp != NULL, ("tcp6_usr_listen: inp == NULL"));
413 	INP_WLOCK(inp);
414 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
415 		error = EINVAL;
416 		goto out;
417 	}
418 	tp = intotcpcb(inp);
419 	TCPDEBUG1();
420 	SOCK_LOCK(so);
421 	error = solisten_proto_check(so);
422 	INP_HASH_WLOCK(&V_tcbinfo);
423 	if (error == 0 && inp->inp_lport == 0) {
424 		inp->inp_vflag &= ~INP_IPV4;
425 		if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
426 			inp->inp_vflag |= INP_IPV4;
427 		error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
428 	}
429 	INP_HASH_WUNLOCK(&V_tcbinfo);
430 	if (error == 0) {
431 		tcp_state_change(tp, TCPS_LISTEN);
432 		solisten_proto(so, backlog);
433 #ifdef TCP_OFFLOAD
434 		if ((so->so_options & SO_NO_OFFLOAD) == 0)
435 			tcp_offload_listen_start(tp);
436 #endif
437 	}
438 	SOCK_UNLOCK(so);
439 
440 out:
441 	TCPDEBUG2(PRU_LISTEN);
442 	INP_WUNLOCK(inp);
443 	return (error);
444 }
445 #endif /* INET6 */
446 
447 #ifdef INET
448 /*
449  * Initiate connection to peer.
450  * Create a template for use in transmissions on this connection.
451  * Enter SYN_SENT state, and mark socket as connecting.
452  * Start keep-alive timer, and seed output sequence space.
453  * Send initial segment on connection.
454  */
455 static int
456 tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
457 {
458 	int error = 0;
459 	struct inpcb *inp;
460 	struct tcpcb *tp = NULL;
461 	struct sockaddr_in *sinp;
462 
463 	sinp = (struct sockaddr_in *)nam;
464 	if (nam->sa_len != sizeof (*sinp))
465 		return (EINVAL);
466 	/*
467 	 * Must disallow TCP ``connections'' to multicast addresses.
468 	 */
469 	if (sinp->sin_family == AF_INET
470 	    && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
471 		return (EAFNOSUPPORT);
472 	if ((error = prison_remote_ip4(td->td_ucred, &sinp->sin_addr)) != 0)
473 		return (error);
474 
475 	TCPDEBUG0;
476 	inp = sotoinpcb(so);
477 	KASSERT(inp != NULL, ("tcp_usr_connect: inp == NULL"));
478 	INP_WLOCK(inp);
479 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
480 		error = EINVAL;
481 		goto out;
482 	}
483 	tp = intotcpcb(inp);
484 	TCPDEBUG1();
485 	if ((error = tcp_connect(tp, nam, td)) != 0)
486 		goto out;
487 #ifdef TCP_OFFLOAD
488 	if (registered_toedevs > 0 &&
489 	    (so->so_options & SO_NO_OFFLOAD) == 0 &&
490 	    (error = tcp_offload_connect(so, nam)) == 0)
491 		goto out;
492 #endif
493 	tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
494 	error = tcp_output(tp);
495 out:
496 	TCPDEBUG2(PRU_CONNECT);
497 	INP_WUNLOCK(inp);
498 	return (error);
499 }
500 #endif /* INET */
501 
502 #ifdef INET6
503 static int
504 tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
505 {
506 	int error = 0;
507 	struct inpcb *inp;
508 	struct tcpcb *tp = NULL;
509 	struct sockaddr_in6 *sin6p;
510 
511 	TCPDEBUG0;
512 
513 	sin6p = (struct sockaddr_in6 *)nam;
514 	if (nam->sa_len != sizeof (*sin6p))
515 		return (EINVAL);
516 	/*
517 	 * Must disallow TCP ``connections'' to multicast addresses.
518 	 */
519 	if (sin6p->sin6_family == AF_INET6
520 	    && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr))
521 		return (EAFNOSUPPORT);
522 
523 	inp = sotoinpcb(so);
524 	KASSERT(inp != NULL, ("tcp6_usr_connect: inp == NULL"));
525 	INP_WLOCK(inp);
526 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
527 		error = EINVAL;
528 		goto out;
529 	}
530 	tp = intotcpcb(inp);
531 	TCPDEBUG1();
532 #ifdef INET
533 	/*
534 	 * XXXRW: Some confusion: V4/V6 flags relate to binding, and
535 	 * therefore probably require the hash lock, which isn't held here.
536 	 * Is this a significant problem?
537 	 */
538 	if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
539 		struct sockaddr_in sin;
540 
541 		if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
542 			error = EINVAL;
543 			goto out;
544 		}
545 
546 		in6_sin6_2_sin(&sin, sin6p);
547 		inp->inp_vflag |= INP_IPV4;
548 		inp->inp_vflag &= ~INP_IPV6;
549 		if ((error = prison_remote_ip4(td->td_ucred,
550 		    &sin.sin_addr)) != 0)
551 			goto out;
552 		if ((error = tcp_connect(tp, (struct sockaddr *)&sin, td)) != 0)
553 			goto out;
554 #ifdef TCP_OFFLOAD
555 		if (registered_toedevs > 0 &&
556 		    (so->so_options & SO_NO_OFFLOAD) == 0 &&
557 		    (error = tcp_offload_connect(so, nam)) == 0)
558 			goto out;
559 #endif
560 		error = tcp_output(tp);
561 		goto out;
562 	}
563 #endif
564 	inp->inp_vflag &= ~INP_IPV4;
565 	inp->inp_vflag |= INP_IPV6;
566 	inp->inp_inc.inc_flags |= INC_ISIPV6;
567 	if ((error = prison_remote_ip6(td->td_ucred, &sin6p->sin6_addr)) != 0)
568 		goto out;
569 	if ((error = tcp6_connect(tp, nam, td)) != 0)
570 		goto out;
571 #ifdef TCP_OFFLOAD
572 	if (registered_toedevs > 0 &&
573 	    (so->so_options & SO_NO_OFFLOAD) == 0 &&
574 	    (error = tcp_offload_connect(so, nam)) == 0)
575 		goto out;
576 #endif
577 	tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
578 	error = tcp_output(tp);
579 
580 out:
581 	TCPDEBUG2(PRU_CONNECT);
582 	INP_WUNLOCK(inp);
583 	return (error);
584 }
585 #endif /* INET6 */
586 
587 /*
588  * Initiate disconnect from peer.
589  * If connection never passed embryonic stage, just drop;
590  * else if don't need to let data drain, then can just drop anyways,
591  * else have to begin TCP shutdown process: mark socket disconnecting,
592  * drain unread data, state switch to reflect user close, and
593  * send segment (e.g. FIN) to peer.  Socket will be really disconnected
594  * when peer sends FIN and acks ours.
595  *
596  * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.
597  */
598 static int
599 tcp_usr_disconnect(struct socket *so)
600 {
601 	struct inpcb *inp;
602 	struct tcpcb *tp = NULL;
603 	int error = 0;
604 
605 	TCPDEBUG0;
606 	INP_INFO_WLOCK(&V_tcbinfo);
607 	inp = sotoinpcb(so);
608 	KASSERT(inp != NULL, ("tcp_usr_disconnect: inp == NULL"));
609 	INP_WLOCK(inp);
610 	if (inp->inp_flags & INP_TIMEWAIT)
611 		goto out;
612 	if (inp->inp_flags & INP_DROPPED) {
613 		error = ECONNRESET;
614 		goto out;
615 	}
616 	tp = intotcpcb(inp);
617 	TCPDEBUG1();
618 	tcp_disconnect(tp);
619 out:
620 	TCPDEBUG2(PRU_DISCONNECT);
621 	INP_WUNLOCK(inp);
622 	INP_INFO_WUNLOCK(&V_tcbinfo);
623 	return (error);
624 }
625 
626 #ifdef INET
627 /*
628  * Accept a connection.  Essentially all the work is done at higher levels;
629  * just return the address of the peer, storing through addr.
630  */
631 static int
632 tcp_usr_accept(struct socket *so, struct sockaddr **nam)
633 {
634 	int error = 0;
635 	struct inpcb *inp = NULL;
636 	struct tcpcb *tp = NULL;
637 	struct in_addr addr;
638 	in_port_t port = 0;
639 	TCPDEBUG0;
640 
641 	if (so->so_state & SS_ISDISCONNECTED)
642 		return (ECONNABORTED);
643 
644 	inp = sotoinpcb(so);
645 	KASSERT(inp != NULL, ("tcp_usr_accept: inp == NULL"));
646 	INP_WLOCK(inp);
647 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
648 		error = ECONNABORTED;
649 		goto out;
650 	}
651 	tp = intotcpcb(inp);
652 	TCPDEBUG1();
653 
654 	/*
655 	 * We inline in_getpeeraddr and COMMON_END here, so that we can
656 	 * copy the data of interest and defer the malloc until after we
657 	 * release the lock.
658 	 */
659 	port = inp->inp_fport;
660 	addr = inp->inp_faddr;
661 
662 out:
663 	TCPDEBUG2(PRU_ACCEPT);
664 	INP_WUNLOCK(inp);
665 	if (error == 0)
666 		*nam = in_sockaddr(port, &addr);
667 	return error;
668 }
669 #endif /* INET */
670 
671 #ifdef INET6
672 static int
673 tcp6_usr_accept(struct socket *so, struct sockaddr **nam)
674 {
675 	struct inpcb *inp = NULL;
676 	int error = 0;
677 	struct tcpcb *tp = NULL;
678 	struct in_addr addr;
679 	struct in6_addr addr6;
680 	in_port_t port = 0;
681 	int v4 = 0;
682 	TCPDEBUG0;
683 
684 	if (so->so_state & SS_ISDISCONNECTED)
685 		return (ECONNABORTED);
686 
687 	inp = sotoinpcb(so);
688 	KASSERT(inp != NULL, ("tcp6_usr_accept: inp == NULL"));
689 	INP_INFO_RLOCK(&V_tcbinfo);
690 	INP_WLOCK(inp);
691 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
692 		error = ECONNABORTED;
693 		goto out;
694 	}
695 	tp = intotcpcb(inp);
696 	TCPDEBUG1();
697 
698 	/*
699 	 * We inline in6_mapped_peeraddr and COMMON_END here, so that we can
700 	 * copy the data of interest and defer the malloc until after we
701 	 * release the lock.
702 	 */
703 	if (inp->inp_vflag & INP_IPV4) {
704 		v4 = 1;
705 		port = inp->inp_fport;
706 		addr = inp->inp_faddr;
707 	} else {
708 		port = inp->inp_fport;
709 		addr6 = inp->in6p_faddr;
710 	}
711 
712 out:
713 	TCPDEBUG2(PRU_ACCEPT);
714 	INP_WUNLOCK(inp);
715 	INP_INFO_RUNLOCK(&V_tcbinfo);
716 	if (error == 0) {
717 		if (v4)
718 			*nam = in6_v4mapsin6_sockaddr(port, &addr);
719 		else
720 			*nam = in6_sockaddr(port, &addr6);
721 	}
722 	return error;
723 }
724 #endif /* INET6 */
725 
726 /*
727  * Mark the connection as being incapable of further output.
728  */
729 static int
730 tcp_usr_shutdown(struct socket *so)
731 {
732 	int error = 0;
733 	struct inpcb *inp;
734 	struct tcpcb *tp = NULL;
735 
736 	TCPDEBUG0;
737 	INP_INFO_WLOCK(&V_tcbinfo);
738 	inp = sotoinpcb(so);
739 	KASSERT(inp != NULL, ("inp == NULL"));
740 	INP_WLOCK(inp);
741 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
742 		error = ECONNRESET;
743 		goto out;
744 	}
745 	tp = intotcpcb(inp);
746 	TCPDEBUG1();
747 	socantsendmore(so);
748 	tcp_usrclosed(tp);
749 	if (!(inp->inp_flags & INP_DROPPED))
750 		error = tcp_output(tp);
751 
752 out:
753 	TCPDEBUG2(PRU_SHUTDOWN);
754 	INP_WUNLOCK(inp);
755 	INP_INFO_WUNLOCK(&V_tcbinfo);
756 
757 	return (error);
758 }
759 
760 /*
761  * After a receive, possibly send window update to peer.
762  */
763 static int
764 tcp_usr_rcvd(struct socket *so, int flags)
765 {
766 	struct inpcb *inp;
767 	struct tcpcb *tp = NULL;
768 	int error = 0;
769 
770 	TCPDEBUG0;
771 	inp = sotoinpcb(so);
772 	KASSERT(inp != NULL, ("tcp_usr_rcvd: inp == NULL"));
773 	INP_WLOCK(inp);
774 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
775 		error = ECONNRESET;
776 		goto out;
777 	}
778 	tp = intotcpcb(inp);
779 	TCPDEBUG1();
780 #ifdef TCP_OFFLOAD
781 	if (tp->t_flags & TF_TOE)
782 		tcp_offload_rcvd(tp);
783 	else
784 #endif
785 	tcp_output(tp);
786 
787 out:
788 	TCPDEBUG2(PRU_RCVD);
789 	INP_WUNLOCK(inp);
790 	return (error);
791 }
792 
793 /*
794  * Do a send by putting data in output queue and updating urgent
795  * marker if URG set.  Possibly send more data.  Unlike the other
796  * pru_*() routines, the mbuf chains are our responsibility.  We
797  * must either enqueue them or free them.  The other pru_* routines
798  * generally are caller-frees.
799  */
800 static int
801 tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
802     struct sockaddr *nam, struct mbuf *control, struct thread *td)
803 {
804 	int error = 0;
805 	struct inpcb *inp;
806 	struct tcpcb *tp = NULL;
807 #ifdef INET6
808 	int isipv6;
809 #endif
810 	TCPDEBUG0;
811 
812 	/*
813 	 * We require the pcbinfo lock if we will close the socket as part of
814 	 * this call.
815 	 */
816 	if (flags & PRUS_EOF)
817 		INP_INFO_WLOCK(&V_tcbinfo);
818 	inp = sotoinpcb(so);
819 	KASSERT(inp != NULL, ("tcp_usr_send: inp == NULL"));
820 	INP_WLOCK(inp);
821 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
822 		if (control)
823 			m_freem(control);
824 		if (m)
825 			m_freem(m);
826 		error = ECONNRESET;
827 		goto out;
828 	}
829 #ifdef INET6
830 	isipv6 = nam && nam->sa_family == AF_INET6;
831 #endif /* INET6 */
832 	tp = intotcpcb(inp);
833 	TCPDEBUG1();
834 	if (control) {
835 		/* TCP doesn't do control messages (rights, creds, etc) */
836 		if (control->m_len) {
837 			m_freem(control);
838 			if (m)
839 				m_freem(m);
840 			error = EINVAL;
841 			goto out;
842 		}
843 		m_freem(control);	/* empty control, just free it */
844 	}
845 	if (!(flags & PRUS_OOB)) {
846 		sbappendstream(&so->so_snd, m);
847 		if (nam && tp->t_state < TCPS_SYN_SENT) {
848 			/*
849 			 * Do implied connect if not yet connected,
850 			 * initialize window to default value, and
851 			 * initialize maxseg/maxopd using peer's cached
852 			 * MSS.
853 			 */
854 #ifdef INET6
855 			if (isipv6)
856 				error = tcp6_connect(tp, nam, td);
857 #endif /* INET6 */
858 #if defined(INET6) && defined(INET)
859 			else
860 #endif
861 #ifdef INET
862 				error = tcp_connect(tp, nam, td);
863 #endif
864 			if (error)
865 				goto out;
866 			tp->snd_wnd = TTCP_CLIENT_SND_WND;
867 			tcp_mss(tp, -1);
868 		}
869 		if (flags & PRUS_EOF) {
870 			/*
871 			 * Close the send side of the connection after
872 			 * the data is sent.
873 			 */
874 			INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
875 			socantsendmore(so);
876 			tcp_usrclosed(tp);
877 		}
878 		if (!(inp->inp_flags & INP_DROPPED)) {
879 			if (flags & PRUS_MORETOCOME)
880 				tp->t_flags |= TF_MORETOCOME;
881 			error = tcp_output(tp);
882 			if (flags & PRUS_MORETOCOME)
883 				tp->t_flags &= ~TF_MORETOCOME;
884 		}
885 	} else {
886 		/*
887 		 * XXXRW: PRUS_EOF not implemented with PRUS_OOB?
888 		 */
889 		SOCKBUF_LOCK(&so->so_snd);
890 		if (sbspace(&so->so_snd) < -512) {
891 			SOCKBUF_UNLOCK(&so->so_snd);
892 			m_freem(m);
893 			error = ENOBUFS;
894 			goto out;
895 		}
896 		/*
897 		 * According to RFC961 (Assigned Protocols),
898 		 * the urgent pointer points to the last octet
899 		 * of urgent data.  We continue, however,
900 		 * to consider it to indicate the first octet
901 		 * of data past the urgent section.
902 		 * Otherwise, snd_up should be one lower.
903 		 */
904 		sbappendstream_locked(&so->so_snd, m);
905 		SOCKBUF_UNLOCK(&so->so_snd);
906 		if (nam && tp->t_state < TCPS_SYN_SENT) {
907 			/*
908 			 * Do implied connect if not yet connected,
909 			 * initialize window to default value, and
910 			 * initialize maxseg/maxopd using peer's cached
911 			 * MSS.
912 			 */
913 #ifdef INET6
914 			if (isipv6)
915 				error = tcp6_connect(tp, nam, td);
916 #endif /* INET6 */
917 #if defined(INET6) && defined(INET)
918 			else
919 #endif
920 #ifdef INET
921 				error = tcp_connect(tp, nam, td);
922 #endif
923 			if (error)
924 				goto out;
925 			tp->snd_wnd = TTCP_CLIENT_SND_WND;
926 			tcp_mss(tp, -1);
927 		}
928 		tp->snd_up = tp->snd_una + sbavail(&so->so_snd);
929 		tp->t_flags |= TF_FORCEDATA;
930 		error = tcp_output(tp);
931 		tp->t_flags &= ~TF_FORCEDATA;
932 	}
933 out:
934 	TCPDEBUG2((flags & PRUS_OOB) ? PRU_SENDOOB :
935 		  ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
936 	INP_WUNLOCK(inp);
937 	if (flags & PRUS_EOF)
938 		INP_INFO_WUNLOCK(&V_tcbinfo);
939 	return (error);
940 }
941 
942 /*
943  * Abort the TCP.  Drop the connection abruptly.
944  */
945 static void
946 tcp_usr_abort(struct socket *so)
947 {
948 	struct inpcb *inp;
949 	struct tcpcb *tp = NULL;
950 	TCPDEBUG0;
951 
952 	inp = sotoinpcb(so);
953 	KASSERT(inp != NULL, ("tcp_usr_abort: inp == NULL"));
954 
955 	INP_INFO_WLOCK(&V_tcbinfo);
956 	INP_WLOCK(inp);
957 	KASSERT(inp->inp_socket != NULL,
958 	    ("tcp_usr_abort: inp_socket == NULL"));
959 
960 	/*
961 	 * If we still have full TCP state, and we're not dropped, drop.
962 	 */
963 	if (!(inp->inp_flags & INP_TIMEWAIT) &&
964 	    !(inp->inp_flags & INP_DROPPED)) {
965 		tp = intotcpcb(inp);
966 		TCPDEBUG1();
967 		tcp_drop(tp, ECONNABORTED);
968 		TCPDEBUG2(PRU_ABORT);
969 	}
970 	if (!(inp->inp_flags & INP_DROPPED)) {
971 		SOCK_LOCK(so);
972 		so->so_state |= SS_PROTOREF;
973 		SOCK_UNLOCK(so);
974 		inp->inp_flags |= INP_SOCKREF;
975 	}
976 	INP_WUNLOCK(inp);
977 	INP_INFO_WUNLOCK(&V_tcbinfo);
978 }
979 
980 /*
981  * TCP socket is closed.  Start friendly disconnect.
982  */
983 static void
984 tcp_usr_close(struct socket *so)
985 {
986 	struct inpcb *inp;
987 	struct tcpcb *tp = NULL;
988 	TCPDEBUG0;
989 
990 	inp = sotoinpcb(so);
991 	KASSERT(inp != NULL, ("tcp_usr_close: inp == NULL"));
992 
993 	INP_INFO_WLOCK(&V_tcbinfo);
994 	INP_WLOCK(inp);
995 	KASSERT(inp->inp_socket != NULL,
996 	    ("tcp_usr_close: inp_socket == NULL"));
997 
998 	/*
999 	 * If we still have full TCP state, and we're not dropped, initiate
1000 	 * a disconnect.
1001 	 */
1002 	if (!(inp->inp_flags & INP_TIMEWAIT) &&
1003 	    !(inp->inp_flags & INP_DROPPED)) {
1004 		tp = intotcpcb(inp);
1005 		TCPDEBUG1();
1006 		tcp_disconnect(tp);
1007 		TCPDEBUG2(PRU_CLOSE);
1008 	}
1009 	if (!(inp->inp_flags & INP_DROPPED)) {
1010 		SOCK_LOCK(so);
1011 		so->so_state |= SS_PROTOREF;
1012 		SOCK_UNLOCK(so);
1013 		inp->inp_flags |= INP_SOCKREF;
1014 	}
1015 	INP_WUNLOCK(inp);
1016 	INP_INFO_WUNLOCK(&V_tcbinfo);
1017 }
1018 
1019 /*
1020  * Receive out-of-band data.
1021  */
1022 static int
1023 tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags)
1024 {
1025 	int error = 0;
1026 	struct inpcb *inp;
1027 	struct tcpcb *tp = NULL;
1028 
1029 	TCPDEBUG0;
1030 	inp = sotoinpcb(so);
1031 	KASSERT(inp != NULL, ("tcp_usr_rcvoob: inp == NULL"));
1032 	INP_WLOCK(inp);
1033 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1034 		error = ECONNRESET;
1035 		goto out;
1036 	}
1037 	tp = intotcpcb(inp);
1038 	TCPDEBUG1();
1039 	if ((so->so_oobmark == 0 &&
1040 	     (so->so_rcv.sb_state & SBS_RCVATMARK) == 0) ||
1041 	    so->so_options & SO_OOBINLINE ||
1042 	    tp->t_oobflags & TCPOOB_HADDATA) {
1043 		error = EINVAL;
1044 		goto out;
1045 	}
1046 	if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
1047 		error = EWOULDBLOCK;
1048 		goto out;
1049 	}
1050 	m->m_len = 1;
1051 	*mtod(m, caddr_t) = tp->t_iobc;
1052 	if ((flags & MSG_PEEK) == 0)
1053 		tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
1054 
1055 out:
1056 	TCPDEBUG2(PRU_RCVOOB);
1057 	INP_WUNLOCK(inp);
1058 	return (error);
1059 }
1060 
1061 #ifdef INET
1062 struct pr_usrreqs tcp_usrreqs = {
1063 	.pru_abort =		tcp_usr_abort,
1064 	.pru_accept =		tcp_usr_accept,
1065 	.pru_attach =		tcp_usr_attach,
1066 	.pru_bind =		tcp_usr_bind,
1067 	.pru_connect =		tcp_usr_connect,
1068 	.pru_control =		in_control,
1069 	.pru_detach =		tcp_usr_detach,
1070 	.pru_disconnect =	tcp_usr_disconnect,
1071 	.pru_listen =		tcp_usr_listen,
1072 	.pru_peeraddr =		in_getpeeraddr,
1073 	.pru_rcvd =		tcp_usr_rcvd,
1074 	.pru_rcvoob =		tcp_usr_rcvoob,
1075 	.pru_send =		tcp_usr_send,
1076 	.pru_shutdown =		tcp_usr_shutdown,
1077 	.pru_sockaddr =		in_getsockaddr,
1078 	.pru_sosetlabel =	in_pcbsosetlabel,
1079 	.pru_close =		tcp_usr_close,
1080 };
1081 #endif /* INET */
1082 
1083 #ifdef INET6
1084 struct pr_usrreqs tcp6_usrreqs = {
1085 	.pru_abort =		tcp_usr_abort,
1086 	.pru_accept =		tcp6_usr_accept,
1087 	.pru_attach =		tcp_usr_attach,
1088 	.pru_bind =		tcp6_usr_bind,
1089 	.pru_connect =		tcp6_usr_connect,
1090 	.pru_control =		in6_control,
1091 	.pru_detach =		tcp_usr_detach,
1092 	.pru_disconnect =	tcp_usr_disconnect,
1093 	.pru_listen =		tcp6_usr_listen,
1094 	.pru_peeraddr =		in6_mapped_peeraddr,
1095 	.pru_rcvd =		tcp_usr_rcvd,
1096 	.pru_rcvoob =		tcp_usr_rcvoob,
1097 	.pru_send =		tcp_usr_send,
1098 	.pru_shutdown =		tcp_usr_shutdown,
1099 	.pru_sockaddr =		in6_mapped_sockaddr,
1100 	.pru_sosetlabel =	in_pcbsosetlabel,
1101 	.pru_close =		tcp_usr_close,
1102 };
1103 #endif /* INET6 */
1104 
1105 #ifdef INET
1106 /*
1107  * Common subroutine to open a TCP connection to remote host specified
1108  * by struct sockaddr_in in mbuf *nam.  Call in_pcbbind to assign a local
1109  * port number if needed.  Call in_pcbconnect_setup to do the routing and
1110  * to choose a local host address (interface).  If there is an existing
1111  * incarnation of the same connection in TIME-WAIT state and if the remote
1112  * host was sending CC options and if the connection duration was < MSL, then
1113  * truncate the previous TIME-WAIT state and proceed.
1114  * Initialize connection parameters and enter SYN-SENT state.
1115  */
1116 static int
1117 tcp_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1118 {
1119 	struct inpcb *inp = tp->t_inpcb, *oinp;
1120 	struct socket *so = inp->inp_socket;
1121 	struct in_addr laddr;
1122 	u_short lport;
1123 	int error;
1124 
1125 	INP_WLOCK_ASSERT(inp);
1126 	INP_HASH_WLOCK(&V_tcbinfo);
1127 
1128 	if (inp->inp_lport == 0) {
1129 		error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1130 		if (error)
1131 			goto out;
1132 	}
1133 
1134 	/*
1135 	 * Cannot simply call in_pcbconnect, because there might be an
1136 	 * earlier incarnation of this same connection still in
1137 	 * TIME_WAIT state, creating an ADDRINUSE error.
1138 	 */
1139 	laddr = inp->inp_laddr;
1140 	lport = inp->inp_lport;
1141 	error = in_pcbconnect_setup(inp, nam, &laddr.s_addr, &lport,
1142 	    &inp->inp_faddr.s_addr, &inp->inp_fport, &oinp, td->td_ucred);
1143 	if (error && oinp == NULL)
1144 		goto out;
1145 	if (oinp) {
1146 		error = EADDRINUSE;
1147 		goto out;
1148 	}
1149 	inp->inp_laddr = laddr;
1150 	in_pcbrehash(inp);
1151 	INP_HASH_WUNLOCK(&V_tcbinfo);
1152 
1153 	/*
1154 	 * Compute window scaling to request:
1155 	 * Scale to fit into sweet spot.  See tcp_syncache.c.
1156 	 * XXX: This should move to tcp_output().
1157 	 */
1158 	while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1159 	    (TCP_MAXWIN << tp->request_r_scale) < sb_max)
1160 		tp->request_r_scale++;
1161 
1162 	soisconnecting(so);
1163 	TCPSTAT_INC(tcps_connattempt);
1164 	tcp_state_change(tp, TCPS_SYN_SENT);
1165 	tp->iss = tcp_new_isn(tp);
1166 	tcp_sendseqinit(tp);
1167 
1168 	return 0;
1169 
1170 out:
1171 	INP_HASH_WUNLOCK(&V_tcbinfo);
1172 	return (error);
1173 }
1174 #endif /* INET */
1175 
1176 #ifdef INET6
1177 static int
1178 tcp6_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1179 {
1180 	struct inpcb *inp = tp->t_inpcb;
1181 	int error;
1182 
1183 	INP_WLOCK_ASSERT(inp);
1184 	INP_HASH_WLOCK(&V_tcbinfo);
1185 
1186 	if (inp->inp_lport == 0) {
1187 		error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1188 		if (error)
1189 			goto out;
1190 	}
1191 	error = in6_pcbconnect(inp, nam, td->td_ucred);
1192 	if (error != 0)
1193 		goto out;
1194 	INP_HASH_WUNLOCK(&V_tcbinfo);
1195 
1196 	/* Compute window scaling to request.  */
1197 	while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1198 	    (TCP_MAXWIN << tp->request_r_scale) < sb_max)
1199 		tp->request_r_scale++;
1200 
1201 	soisconnecting(inp->inp_socket);
1202 	TCPSTAT_INC(tcps_connattempt);
1203 	tcp_state_change(tp, TCPS_SYN_SENT);
1204 	tp->iss = tcp_new_isn(tp);
1205 	tcp_sendseqinit(tp);
1206 
1207 	return 0;
1208 
1209 out:
1210 	INP_HASH_WUNLOCK(&V_tcbinfo);
1211 	return error;
1212 }
1213 #endif /* INET6 */
1214 
1215 /*
1216  * Export TCP internal state information via a struct tcp_info, based on the
1217  * Linux 2.6 API.  Not ABI compatible as our constants are mapped differently
1218  * (TCP state machine, etc).  We export all information using FreeBSD-native
1219  * constants -- for example, the numeric values for tcpi_state will differ
1220  * from Linux.
1221  */
1222 static void
1223 tcp_fill_info(struct tcpcb *tp, struct tcp_info *ti)
1224 {
1225 
1226 	INP_WLOCK_ASSERT(tp->t_inpcb);
1227 	bzero(ti, sizeof(*ti));
1228 
1229 	ti->tcpi_state = tp->t_state;
1230 	if ((tp->t_flags & TF_REQ_TSTMP) && (tp->t_flags & TF_RCVD_TSTMP))
1231 		ti->tcpi_options |= TCPI_OPT_TIMESTAMPS;
1232 	if (tp->t_flags & TF_SACK_PERMIT)
1233 		ti->tcpi_options |= TCPI_OPT_SACK;
1234 	if ((tp->t_flags & TF_REQ_SCALE) && (tp->t_flags & TF_RCVD_SCALE)) {
1235 		ti->tcpi_options |= TCPI_OPT_WSCALE;
1236 		ti->tcpi_snd_wscale = tp->snd_scale;
1237 		ti->tcpi_rcv_wscale = tp->rcv_scale;
1238 	}
1239 
1240 	ti->tcpi_rto = tp->t_rxtcur * tick;
1241 	ti->tcpi_last_data_recv = (long)(ticks - (int)tp->t_rcvtime) * tick;
1242 	ti->tcpi_rtt = ((u_int64_t)tp->t_srtt * tick) >> TCP_RTT_SHIFT;
1243 	ti->tcpi_rttvar = ((u_int64_t)tp->t_rttvar * tick) >> TCP_RTTVAR_SHIFT;
1244 
1245 	ti->tcpi_snd_ssthresh = tp->snd_ssthresh;
1246 	ti->tcpi_snd_cwnd = tp->snd_cwnd;
1247 
1248 	/*
1249 	 * FreeBSD-specific extension fields for tcp_info.
1250 	 */
1251 	ti->tcpi_rcv_space = tp->rcv_wnd;
1252 	ti->tcpi_rcv_nxt = tp->rcv_nxt;
1253 	ti->tcpi_snd_wnd = tp->snd_wnd;
1254 	ti->tcpi_snd_bwnd = 0;		/* Unused, kept for compat. */
1255 	ti->tcpi_snd_nxt = tp->snd_nxt;
1256 	ti->tcpi_snd_mss = tp->t_maxseg;
1257 	ti->tcpi_rcv_mss = tp->t_maxseg;
1258 	if (tp->t_flags & TF_TOE)
1259 		ti->tcpi_options |= TCPI_OPT_TOE;
1260 	ti->tcpi_snd_rexmitpack = tp->t_sndrexmitpack;
1261 	ti->tcpi_rcv_ooopack = tp->t_rcvoopack;
1262 	ti->tcpi_snd_zerowin = tp->t_sndzerowin;
1263 }
1264 
1265 /*
1266  * tcp_ctloutput() must drop the inpcb lock before performing copyin on
1267  * socket option arguments.  When it re-acquires the lock after the copy, it
1268  * has to revalidate that the connection is still valid for the socket
1269  * option.
1270  */
1271 #define INP_WLOCK_RECHECK(inp) do {					\
1272 	INP_WLOCK(inp);							\
1273 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {		\
1274 		INP_WUNLOCK(inp);					\
1275 		return (ECONNRESET);					\
1276 	}								\
1277 	tp = intotcpcb(inp);						\
1278 } while(0)
1279 
1280 int
1281 tcp_ctloutput(struct socket *so, struct sockopt *sopt)
1282 {
1283 	int	error, opt, optval;
1284 	u_int	ui;
1285 	struct	inpcb *inp;
1286 	struct	tcpcb *tp;
1287 	struct	tcp_info ti;
1288 	char buf[TCP_CA_NAME_MAX];
1289 	struct cc_algo *algo;
1290 
1291 	error = 0;
1292 	inp = sotoinpcb(so);
1293 	KASSERT(inp != NULL, ("tcp_ctloutput: inp == NULL"));
1294 	INP_WLOCK(inp);
1295 	if (sopt->sopt_level != IPPROTO_TCP) {
1296 #ifdef INET6
1297 		if (inp->inp_vflag & INP_IPV6PROTO) {
1298 			INP_WUNLOCK(inp);
1299 			error = ip6_ctloutput(so, sopt);
1300 		}
1301 #endif /* INET6 */
1302 #if defined(INET6) && defined(INET)
1303 		else
1304 #endif
1305 #ifdef INET
1306 		{
1307 			INP_WUNLOCK(inp);
1308 			error = ip_ctloutput(so, sopt);
1309 		}
1310 #endif
1311 		return (error);
1312 	}
1313 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1314 		INP_WUNLOCK(inp);
1315 		return (ECONNRESET);
1316 	}
1317 
1318 	switch (sopt->sopt_dir) {
1319 	case SOPT_SET:
1320 		switch (sopt->sopt_name) {
1321 #ifdef TCP_SIGNATURE
1322 		case TCP_MD5SIG:
1323 			INP_WUNLOCK(inp);
1324 			error = sooptcopyin(sopt, &optval, sizeof optval,
1325 			    sizeof optval);
1326 			if (error)
1327 				return (error);
1328 
1329 			INP_WLOCK_RECHECK(inp);
1330 			if (optval > 0)
1331 				tp->t_flags |= TF_SIGNATURE;
1332 			else
1333 				tp->t_flags &= ~TF_SIGNATURE;
1334 			goto unlock_and_done;
1335 #endif /* TCP_SIGNATURE */
1336 
1337 		case TCP_NODELAY:
1338 		case TCP_NOOPT:
1339 			INP_WUNLOCK(inp);
1340 			error = sooptcopyin(sopt, &optval, sizeof optval,
1341 			    sizeof optval);
1342 			if (error)
1343 				return (error);
1344 
1345 			INP_WLOCK_RECHECK(inp);
1346 			switch (sopt->sopt_name) {
1347 			case TCP_NODELAY:
1348 				opt = TF_NODELAY;
1349 				break;
1350 			case TCP_NOOPT:
1351 				opt = TF_NOOPT;
1352 				break;
1353 			default:
1354 				opt = 0; /* dead code to fool gcc */
1355 				break;
1356 			}
1357 
1358 			if (optval)
1359 				tp->t_flags |= opt;
1360 			else
1361 				tp->t_flags &= ~opt;
1362 unlock_and_done:
1363 #ifdef TCP_OFFLOAD
1364 			if (tp->t_flags & TF_TOE) {
1365 				tcp_offload_ctloutput(tp, sopt->sopt_dir,
1366 				    sopt->sopt_name);
1367 			}
1368 #endif
1369 			INP_WUNLOCK(inp);
1370 			break;
1371 
1372 		case TCP_NOPUSH:
1373 			INP_WUNLOCK(inp);
1374 			error = sooptcopyin(sopt, &optval, sizeof optval,
1375 			    sizeof optval);
1376 			if (error)
1377 				return (error);
1378 
1379 			INP_WLOCK_RECHECK(inp);
1380 			if (optval)
1381 				tp->t_flags |= TF_NOPUSH;
1382 			else if (tp->t_flags & TF_NOPUSH) {
1383 				tp->t_flags &= ~TF_NOPUSH;
1384 				if (TCPS_HAVEESTABLISHED(tp->t_state))
1385 					error = tcp_output(tp);
1386 			}
1387 			goto unlock_and_done;
1388 
1389 		case TCP_MAXSEG:
1390 			INP_WUNLOCK(inp);
1391 			error = sooptcopyin(sopt, &optval, sizeof optval,
1392 			    sizeof optval);
1393 			if (error)
1394 				return (error);
1395 
1396 			INP_WLOCK_RECHECK(inp);
1397 			if (optval > 0 && optval <= tp->t_maxseg &&
1398 			    optval + 40 >= V_tcp_minmss)
1399 				tp->t_maxseg = optval;
1400 			else
1401 				error = EINVAL;
1402 			goto unlock_and_done;
1403 
1404 		case TCP_INFO:
1405 			INP_WUNLOCK(inp);
1406 			error = EINVAL;
1407 			break;
1408 
1409 		case TCP_CONGESTION:
1410 			INP_WUNLOCK(inp);
1411 			bzero(buf, sizeof(buf));
1412 			error = sooptcopyin(sopt, &buf, sizeof(buf), 1);
1413 			if (error)
1414 				break;
1415 			INP_WLOCK_RECHECK(inp);
1416 			/*
1417 			 * Return EINVAL if we can't find the requested cc algo.
1418 			 */
1419 			error = EINVAL;
1420 			CC_LIST_RLOCK();
1421 			STAILQ_FOREACH(algo, &cc_list, entries) {
1422 				if (strncmp(buf, algo->name, TCP_CA_NAME_MAX)
1423 				    == 0) {
1424 					/* We've found the requested algo. */
1425 					error = 0;
1426 					/*
1427 					 * We hold a write lock over the tcb
1428 					 * so it's safe to do these things
1429 					 * without ordering concerns.
1430 					 */
1431 					if (CC_ALGO(tp)->cb_destroy != NULL)
1432 						CC_ALGO(tp)->cb_destroy(tp->ccv);
1433 					CC_ALGO(tp) = algo;
1434 					/*
1435 					 * If something goes pear shaped
1436 					 * initialising the new algo,
1437 					 * fall back to newreno (which
1438 					 * does not require initialisation).
1439 					 */
1440 					if (algo->cb_init != NULL)
1441 						if (algo->cb_init(tp->ccv) > 0) {
1442 							CC_ALGO(tp) = &newreno_cc_algo;
1443 							/*
1444 							 * The only reason init
1445 							 * should fail is
1446 							 * because of malloc.
1447 							 */
1448 							error = ENOMEM;
1449 						}
1450 					break; /* Break the STAILQ_FOREACH. */
1451 				}
1452 			}
1453 			CC_LIST_RUNLOCK();
1454 			goto unlock_and_done;
1455 
1456 		case TCP_KEEPIDLE:
1457 		case TCP_KEEPINTVL:
1458 		case TCP_KEEPINIT:
1459 			INP_WUNLOCK(inp);
1460 			error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui));
1461 			if (error)
1462 				return (error);
1463 
1464 			if (ui > (UINT_MAX / hz)) {
1465 				error = EINVAL;
1466 				break;
1467 			}
1468 			ui *= hz;
1469 
1470 			INP_WLOCK_RECHECK(inp);
1471 			switch (sopt->sopt_name) {
1472 			case TCP_KEEPIDLE:
1473 				tp->t_keepidle = ui;
1474 				/*
1475 				 * XXX: better check current remaining
1476 				 * timeout and "merge" it with new value.
1477 				 */
1478 				if ((tp->t_state > TCPS_LISTEN) &&
1479 				    (tp->t_state <= TCPS_CLOSING))
1480 					tcp_timer_activate(tp, TT_KEEP,
1481 					    TP_KEEPIDLE(tp));
1482 				break;
1483 			case TCP_KEEPINTVL:
1484 				tp->t_keepintvl = ui;
1485 				if ((tp->t_state == TCPS_FIN_WAIT_2) &&
1486 				    (TP_MAXIDLE(tp) > 0))
1487 					tcp_timer_activate(tp, TT_2MSL,
1488 					    TP_MAXIDLE(tp));
1489 				break;
1490 			case TCP_KEEPINIT:
1491 				tp->t_keepinit = ui;
1492 				if (tp->t_state == TCPS_SYN_RECEIVED ||
1493 				    tp->t_state == TCPS_SYN_SENT)
1494 					tcp_timer_activate(tp, TT_KEEP,
1495 					    TP_KEEPINIT(tp));
1496 				break;
1497 			}
1498 			goto unlock_and_done;
1499 
1500 		case TCP_KEEPCNT:
1501 			INP_WUNLOCK(inp);
1502 			error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui));
1503 			if (error)
1504 				return (error);
1505 
1506 			INP_WLOCK_RECHECK(inp);
1507 			tp->t_keepcnt = ui;
1508 			if ((tp->t_state == TCPS_FIN_WAIT_2) &&
1509 			    (TP_MAXIDLE(tp) > 0))
1510 				tcp_timer_activate(tp, TT_2MSL,
1511 				    TP_MAXIDLE(tp));
1512 			goto unlock_and_done;
1513 
1514 		default:
1515 			INP_WUNLOCK(inp);
1516 			error = ENOPROTOOPT;
1517 			break;
1518 		}
1519 		break;
1520 
1521 	case SOPT_GET:
1522 		tp = intotcpcb(inp);
1523 		switch (sopt->sopt_name) {
1524 #ifdef TCP_SIGNATURE
1525 		case TCP_MD5SIG:
1526 			optval = (tp->t_flags & TF_SIGNATURE) ? 1 : 0;
1527 			INP_WUNLOCK(inp);
1528 			error = sooptcopyout(sopt, &optval, sizeof optval);
1529 			break;
1530 #endif
1531 
1532 		case TCP_NODELAY:
1533 			optval = tp->t_flags & TF_NODELAY;
1534 			INP_WUNLOCK(inp);
1535 			error = sooptcopyout(sopt, &optval, sizeof optval);
1536 			break;
1537 		case TCP_MAXSEG:
1538 			optval = tp->t_maxseg;
1539 			INP_WUNLOCK(inp);
1540 			error = sooptcopyout(sopt, &optval, sizeof optval);
1541 			break;
1542 		case TCP_NOOPT:
1543 			optval = tp->t_flags & TF_NOOPT;
1544 			INP_WUNLOCK(inp);
1545 			error = sooptcopyout(sopt, &optval, sizeof optval);
1546 			break;
1547 		case TCP_NOPUSH:
1548 			optval = tp->t_flags & TF_NOPUSH;
1549 			INP_WUNLOCK(inp);
1550 			error = sooptcopyout(sopt, &optval, sizeof optval);
1551 			break;
1552 		case TCP_INFO:
1553 			tcp_fill_info(tp, &ti);
1554 			INP_WUNLOCK(inp);
1555 			error = sooptcopyout(sopt, &ti, sizeof ti);
1556 			break;
1557 		case TCP_CONGESTION:
1558 			bzero(buf, sizeof(buf));
1559 			strlcpy(buf, CC_ALGO(tp)->name, TCP_CA_NAME_MAX);
1560 			INP_WUNLOCK(inp);
1561 			error = sooptcopyout(sopt, buf, TCP_CA_NAME_MAX);
1562 			break;
1563 		case TCP_KEEPIDLE:
1564 		case TCP_KEEPINTVL:
1565 		case TCP_KEEPINIT:
1566 		case TCP_KEEPCNT:
1567 			switch (sopt->sopt_name) {
1568 			case TCP_KEEPIDLE:
1569 				ui = tp->t_keepidle / hz;
1570 				break;
1571 			case TCP_KEEPINTVL:
1572 				ui = tp->t_keepintvl / hz;
1573 				break;
1574 			case TCP_KEEPINIT:
1575 				ui = tp->t_keepinit / hz;
1576 				break;
1577 			case TCP_KEEPCNT:
1578 				ui = tp->t_keepcnt;
1579 				break;
1580 			}
1581 			INP_WUNLOCK(inp);
1582 			error = sooptcopyout(sopt, &ui, sizeof(ui));
1583 			break;
1584 		default:
1585 			INP_WUNLOCK(inp);
1586 			error = ENOPROTOOPT;
1587 			break;
1588 		}
1589 		break;
1590 	}
1591 	return (error);
1592 }
1593 #undef INP_WLOCK_RECHECK
1594 
1595 /*
1596  * Attach TCP protocol to socket, allocating
1597  * internet protocol control block, tcp control block,
1598  * bufer space, and entering LISTEN state if to accept connections.
1599  */
1600 static int
1601 tcp_attach(struct socket *so)
1602 {
1603 	struct tcpcb *tp;
1604 	struct inpcb *inp;
1605 	int error;
1606 
1607 	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
1608 		error = soreserve(so, V_tcp_sendspace, V_tcp_recvspace);
1609 		if (error)
1610 			return (error);
1611 	}
1612 	so->so_rcv.sb_flags |= SB_AUTOSIZE;
1613 	so->so_snd.sb_flags |= SB_AUTOSIZE;
1614 	INP_INFO_WLOCK(&V_tcbinfo);
1615 	error = in_pcballoc(so, &V_tcbinfo);
1616 	if (error) {
1617 		INP_INFO_WUNLOCK(&V_tcbinfo);
1618 		return (error);
1619 	}
1620 	inp = sotoinpcb(so);
1621 #ifdef INET6
1622 	if (inp->inp_vflag & INP_IPV6PROTO) {
1623 		inp->inp_vflag |= INP_IPV6;
1624 		inp->in6p_hops = -1;	/* use kernel default */
1625 	}
1626 	else
1627 #endif
1628 	inp->inp_vflag |= INP_IPV4;
1629 	tp = tcp_newtcpcb(inp);
1630 	if (tp == NULL) {
1631 		in_pcbdetach(inp);
1632 		in_pcbfree(inp);
1633 		INP_INFO_WUNLOCK(&V_tcbinfo);
1634 		return (ENOBUFS);
1635 	}
1636 	tp->t_state = TCPS_CLOSED;
1637 	INP_WUNLOCK(inp);
1638 	INP_INFO_WUNLOCK(&V_tcbinfo);
1639 	return (0);
1640 }
1641 
1642 /*
1643  * Initiate (or continue) disconnect.
1644  * If embryonic state, just send reset (once).
1645  * If in ``let data drain'' option and linger null, just drop.
1646  * Otherwise (hard), mark socket disconnecting and drop
1647  * current input data; switch states based on user close, and
1648  * send segment to peer (with FIN).
1649  */
1650 static void
1651 tcp_disconnect(struct tcpcb *tp)
1652 {
1653 	struct inpcb *inp = tp->t_inpcb;
1654 	struct socket *so = inp->inp_socket;
1655 
1656 	INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
1657 	INP_WLOCK_ASSERT(inp);
1658 
1659 	/*
1660 	 * Neither tcp_close() nor tcp_drop() should return NULL, as the
1661 	 * socket is still open.
1662 	 */
1663 	if (tp->t_state < TCPS_ESTABLISHED) {
1664 		tp = tcp_close(tp);
1665 		KASSERT(tp != NULL,
1666 		    ("tcp_disconnect: tcp_close() returned NULL"));
1667 	} else if ((so->so_options & SO_LINGER) && so->so_linger == 0) {
1668 		tp = tcp_drop(tp, 0);
1669 		KASSERT(tp != NULL,
1670 		    ("tcp_disconnect: tcp_drop() returned NULL"));
1671 	} else {
1672 		soisdisconnecting(so);
1673 		sbflush(&so->so_rcv);
1674 		tcp_usrclosed(tp);
1675 		if (!(inp->inp_flags & INP_DROPPED))
1676 			tcp_output(tp);
1677 	}
1678 }
1679 
1680 /*
1681  * User issued close, and wish to trail through shutdown states:
1682  * if never received SYN, just forget it.  If got a SYN from peer,
1683  * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
1684  * If already got a FIN from peer, then almost done; go to LAST_ACK
1685  * state.  In all other cases, have already sent FIN to peer (e.g.
1686  * after PRU_SHUTDOWN), and just have to play tedious game waiting
1687  * for peer to send FIN or not respond to keep-alives, etc.
1688  * We can let the user exit from the close as soon as the FIN is acked.
1689  */
1690 static void
1691 tcp_usrclosed(struct tcpcb *tp)
1692 {
1693 
1694 	INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
1695 	INP_WLOCK_ASSERT(tp->t_inpcb);
1696 
1697 	switch (tp->t_state) {
1698 	case TCPS_LISTEN:
1699 #ifdef TCP_OFFLOAD
1700 		tcp_offload_listen_stop(tp);
1701 #endif
1702 		/* FALLTHROUGH */
1703 	case TCPS_CLOSED:
1704 		tcp_state_change(tp, TCPS_CLOSED);
1705 		tp = tcp_close(tp);
1706 		/*
1707 		 * tcp_close() should never return NULL here as the socket is
1708 		 * still open.
1709 		 */
1710 		KASSERT(tp != NULL,
1711 		    ("tcp_usrclosed: tcp_close() returned NULL"));
1712 		break;
1713 
1714 	case TCPS_SYN_SENT:
1715 	case TCPS_SYN_RECEIVED:
1716 		tp->t_flags |= TF_NEEDFIN;
1717 		break;
1718 
1719 	case TCPS_ESTABLISHED:
1720 		tcp_state_change(tp, TCPS_FIN_WAIT_1);
1721 		break;
1722 
1723 	case TCPS_CLOSE_WAIT:
1724 		tcp_state_change(tp, TCPS_LAST_ACK);
1725 		break;
1726 	}
1727 	if (tp->t_state >= TCPS_FIN_WAIT_2) {
1728 		soisdisconnected(tp->t_inpcb->inp_socket);
1729 		/* Prevent the connection hanging in FIN_WAIT_2 forever. */
1730 		if (tp->t_state == TCPS_FIN_WAIT_2) {
1731 			int timeout;
1732 
1733 			timeout = (tcp_fast_finwait2_recycle) ?
1734 			    tcp_finwait2_timeout : TP_MAXIDLE(tp);
1735 			tcp_timer_activate(tp, TT_2MSL, timeout);
1736 		}
1737 	}
1738 }
1739 
1740 #ifdef DDB
1741 static void
1742 db_print_indent(int indent)
1743 {
1744 	int i;
1745 
1746 	for (i = 0; i < indent; i++)
1747 		db_printf(" ");
1748 }
1749 
1750 static void
1751 db_print_tstate(int t_state)
1752 {
1753 
1754 	switch (t_state) {
1755 	case TCPS_CLOSED:
1756 		db_printf("TCPS_CLOSED");
1757 		return;
1758 
1759 	case TCPS_LISTEN:
1760 		db_printf("TCPS_LISTEN");
1761 		return;
1762 
1763 	case TCPS_SYN_SENT:
1764 		db_printf("TCPS_SYN_SENT");
1765 		return;
1766 
1767 	case TCPS_SYN_RECEIVED:
1768 		db_printf("TCPS_SYN_RECEIVED");
1769 		return;
1770 
1771 	case TCPS_ESTABLISHED:
1772 		db_printf("TCPS_ESTABLISHED");
1773 		return;
1774 
1775 	case TCPS_CLOSE_WAIT:
1776 		db_printf("TCPS_CLOSE_WAIT");
1777 		return;
1778 
1779 	case TCPS_FIN_WAIT_1:
1780 		db_printf("TCPS_FIN_WAIT_1");
1781 		return;
1782 
1783 	case TCPS_CLOSING:
1784 		db_printf("TCPS_CLOSING");
1785 		return;
1786 
1787 	case TCPS_LAST_ACK:
1788 		db_printf("TCPS_LAST_ACK");
1789 		return;
1790 
1791 	case TCPS_FIN_WAIT_2:
1792 		db_printf("TCPS_FIN_WAIT_2");
1793 		return;
1794 
1795 	case TCPS_TIME_WAIT:
1796 		db_printf("TCPS_TIME_WAIT");
1797 		return;
1798 
1799 	default:
1800 		db_printf("unknown");
1801 		return;
1802 	}
1803 }
1804 
1805 static void
1806 db_print_tflags(u_int t_flags)
1807 {
1808 	int comma;
1809 
1810 	comma = 0;
1811 	if (t_flags & TF_ACKNOW) {
1812 		db_printf("%sTF_ACKNOW", comma ? ", " : "");
1813 		comma = 1;
1814 	}
1815 	if (t_flags & TF_DELACK) {
1816 		db_printf("%sTF_DELACK", comma ? ", " : "");
1817 		comma = 1;
1818 	}
1819 	if (t_flags & TF_NODELAY) {
1820 		db_printf("%sTF_NODELAY", comma ? ", " : "");
1821 		comma = 1;
1822 	}
1823 	if (t_flags & TF_NOOPT) {
1824 		db_printf("%sTF_NOOPT", comma ? ", " : "");
1825 		comma = 1;
1826 	}
1827 	if (t_flags & TF_SENTFIN) {
1828 		db_printf("%sTF_SENTFIN", comma ? ", " : "");
1829 		comma = 1;
1830 	}
1831 	if (t_flags & TF_REQ_SCALE) {
1832 		db_printf("%sTF_REQ_SCALE", comma ? ", " : "");
1833 		comma = 1;
1834 	}
1835 	if (t_flags & TF_RCVD_SCALE) {
1836 		db_printf("%sTF_RECVD_SCALE", comma ? ", " : "");
1837 		comma = 1;
1838 	}
1839 	if (t_flags & TF_REQ_TSTMP) {
1840 		db_printf("%sTF_REQ_TSTMP", comma ? ", " : "");
1841 		comma = 1;
1842 	}
1843 	if (t_flags & TF_RCVD_TSTMP) {
1844 		db_printf("%sTF_RCVD_TSTMP", comma ? ", " : "");
1845 		comma = 1;
1846 	}
1847 	if (t_flags & TF_SACK_PERMIT) {
1848 		db_printf("%sTF_SACK_PERMIT", comma ? ", " : "");
1849 		comma = 1;
1850 	}
1851 	if (t_flags & TF_NEEDSYN) {
1852 		db_printf("%sTF_NEEDSYN", comma ? ", " : "");
1853 		comma = 1;
1854 	}
1855 	if (t_flags & TF_NEEDFIN) {
1856 		db_printf("%sTF_NEEDFIN", comma ? ", " : "");
1857 		comma = 1;
1858 	}
1859 	if (t_flags & TF_NOPUSH) {
1860 		db_printf("%sTF_NOPUSH", comma ? ", " : "");
1861 		comma = 1;
1862 	}
1863 	if (t_flags & TF_MORETOCOME) {
1864 		db_printf("%sTF_MORETOCOME", comma ? ", " : "");
1865 		comma = 1;
1866 	}
1867 	if (t_flags & TF_LQ_OVERFLOW) {
1868 		db_printf("%sTF_LQ_OVERFLOW", comma ? ", " : "");
1869 		comma = 1;
1870 	}
1871 	if (t_flags & TF_LASTIDLE) {
1872 		db_printf("%sTF_LASTIDLE", comma ? ", " : "");
1873 		comma = 1;
1874 	}
1875 	if (t_flags & TF_RXWIN0SENT) {
1876 		db_printf("%sTF_RXWIN0SENT", comma ? ", " : "");
1877 		comma = 1;
1878 	}
1879 	if (t_flags & TF_FASTRECOVERY) {
1880 		db_printf("%sTF_FASTRECOVERY", comma ? ", " : "");
1881 		comma = 1;
1882 	}
1883 	if (t_flags & TF_CONGRECOVERY) {
1884 		db_printf("%sTF_CONGRECOVERY", comma ? ", " : "");
1885 		comma = 1;
1886 	}
1887 	if (t_flags & TF_WASFRECOVERY) {
1888 		db_printf("%sTF_WASFRECOVERY", comma ? ", " : "");
1889 		comma = 1;
1890 	}
1891 	if (t_flags & TF_SIGNATURE) {
1892 		db_printf("%sTF_SIGNATURE", comma ? ", " : "");
1893 		comma = 1;
1894 	}
1895 	if (t_flags & TF_FORCEDATA) {
1896 		db_printf("%sTF_FORCEDATA", comma ? ", " : "");
1897 		comma = 1;
1898 	}
1899 	if (t_flags & TF_TSO) {
1900 		db_printf("%sTF_TSO", comma ? ", " : "");
1901 		comma = 1;
1902 	}
1903 	if (t_flags & TF_ECN_PERMIT) {
1904 		db_printf("%sTF_ECN_PERMIT", comma ? ", " : "");
1905 		comma = 1;
1906 	}
1907 }
1908 
1909 static void
1910 db_print_toobflags(char t_oobflags)
1911 {
1912 	int comma;
1913 
1914 	comma = 0;
1915 	if (t_oobflags & TCPOOB_HAVEDATA) {
1916 		db_printf("%sTCPOOB_HAVEDATA", comma ? ", " : "");
1917 		comma = 1;
1918 	}
1919 	if (t_oobflags & TCPOOB_HADDATA) {
1920 		db_printf("%sTCPOOB_HADDATA", comma ? ", " : "");
1921 		comma = 1;
1922 	}
1923 }
1924 
1925 static void
1926 db_print_tcpcb(struct tcpcb *tp, const char *name, int indent)
1927 {
1928 
1929 	db_print_indent(indent);
1930 	db_printf("%s at %p\n", name, tp);
1931 
1932 	indent += 2;
1933 
1934 	db_print_indent(indent);
1935 	db_printf("t_segq first: %p   t_segqlen: %d   t_dupacks: %d\n",
1936 	   tp->t_segq, tp->t_segqlen, tp->t_dupacks);
1937 
1938 	db_print_indent(indent);
1939 	db_printf("tt_rexmt: %p   tt_persist: %p   tt_keep: %p\n",
1940 	    &tp->t_timers->tt_rexmt, &tp->t_timers->tt_persist, &tp->t_timers->tt_keep);
1941 
1942 	db_print_indent(indent);
1943 	db_printf("tt_2msl: %p   tt_delack: %p   t_inpcb: %p\n", &tp->t_timers->tt_2msl,
1944 	    &tp->t_timers->tt_delack, tp->t_inpcb);
1945 
1946 	db_print_indent(indent);
1947 	db_printf("t_state: %d (", tp->t_state);
1948 	db_print_tstate(tp->t_state);
1949 	db_printf(")\n");
1950 
1951 	db_print_indent(indent);
1952 	db_printf("t_flags: 0x%x (", tp->t_flags);
1953 	db_print_tflags(tp->t_flags);
1954 	db_printf(")\n");
1955 
1956 	db_print_indent(indent);
1957 	db_printf("snd_una: 0x%08x   snd_max: 0x%08x   snd_nxt: x0%08x\n",
1958 	    tp->snd_una, tp->snd_max, tp->snd_nxt);
1959 
1960 	db_print_indent(indent);
1961 	db_printf("snd_up: 0x%08x   snd_wl1: 0x%08x   snd_wl2: 0x%08x\n",
1962 	   tp->snd_up, tp->snd_wl1, tp->snd_wl2);
1963 
1964 	db_print_indent(indent);
1965 	db_printf("iss: 0x%08x   irs: 0x%08x   rcv_nxt: 0x%08x\n",
1966 	    tp->iss, tp->irs, tp->rcv_nxt);
1967 
1968 	db_print_indent(indent);
1969 	db_printf("rcv_adv: 0x%08x   rcv_wnd: %lu   rcv_up: 0x%08x\n",
1970 	    tp->rcv_adv, tp->rcv_wnd, tp->rcv_up);
1971 
1972 	db_print_indent(indent);
1973 	db_printf("snd_wnd: %lu   snd_cwnd: %lu\n",
1974 	   tp->snd_wnd, tp->snd_cwnd);
1975 
1976 	db_print_indent(indent);
1977 	db_printf("snd_ssthresh: %lu   snd_recover: "
1978 	    "0x%08x\n", tp->snd_ssthresh, tp->snd_recover);
1979 
1980 	db_print_indent(indent);
1981 	db_printf("t_maxopd: %u   t_rcvtime: %u   t_startime: %u\n",
1982 	    tp->t_maxopd, tp->t_rcvtime, tp->t_starttime);
1983 
1984 	db_print_indent(indent);
1985 	db_printf("t_rttime: %u   t_rtsq: 0x%08x\n",
1986 	    tp->t_rtttime, tp->t_rtseq);
1987 
1988 	db_print_indent(indent);
1989 	db_printf("t_rxtcur: %d   t_maxseg: %u   t_srtt: %d\n",
1990 	    tp->t_rxtcur, tp->t_maxseg, tp->t_srtt);
1991 
1992 	db_print_indent(indent);
1993 	db_printf("t_rttvar: %d   t_rxtshift: %d   t_rttmin: %u   "
1994 	    "t_rttbest: %u\n", tp->t_rttvar, tp->t_rxtshift, tp->t_rttmin,
1995 	    tp->t_rttbest);
1996 
1997 	db_print_indent(indent);
1998 	db_printf("t_rttupdated: %lu   max_sndwnd: %lu   t_softerror: %d\n",
1999 	    tp->t_rttupdated, tp->max_sndwnd, tp->t_softerror);
2000 
2001 	db_print_indent(indent);
2002 	db_printf("t_oobflags: 0x%x (", tp->t_oobflags);
2003 	db_print_toobflags(tp->t_oobflags);
2004 	db_printf(")   t_iobc: 0x%02x\n", tp->t_iobc);
2005 
2006 	db_print_indent(indent);
2007 	db_printf("snd_scale: %u   rcv_scale: %u   request_r_scale: %u\n",
2008 	    tp->snd_scale, tp->rcv_scale, tp->request_r_scale);
2009 
2010 	db_print_indent(indent);
2011 	db_printf("ts_recent: %u   ts_recent_age: %u\n",
2012 	    tp->ts_recent, tp->ts_recent_age);
2013 
2014 	db_print_indent(indent);
2015 	db_printf("ts_offset: %u   last_ack_sent: 0x%08x   snd_cwnd_prev: "
2016 	    "%lu\n", tp->ts_offset, tp->last_ack_sent, tp->snd_cwnd_prev);
2017 
2018 	db_print_indent(indent);
2019 	db_printf("snd_ssthresh_prev: %lu   snd_recover_prev: 0x%08x   "
2020 	    "t_badrxtwin: %u\n", tp->snd_ssthresh_prev,
2021 	    tp->snd_recover_prev, tp->t_badrxtwin);
2022 
2023 	db_print_indent(indent);
2024 	db_printf("snd_numholes: %d  snd_holes first: %p\n",
2025 	    tp->snd_numholes, TAILQ_FIRST(&tp->snd_holes));
2026 
2027 	db_print_indent(indent);
2028 	db_printf("snd_fack: 0x%08x   rcv_numsacks: %d   sack_newdata: "
2029 	    "0x%08x\n", tp->snd_fack, tp->rcv_numsacks, tp->sack_newdata);
2030 
2031 	/* Skip sackblks, sackhint. */
2032 
2033 	db_print_indent(indent);
2034 	db_printf("t_rttlow: %d   rfbuf_ts: %u   rfbuf_cnt: %d\n",
2035 	    tp->t_rttlow, tp->rfbuf_ts, tp->rfbuf_cnt);
2036 }
2037 
2038 DB_SHOW_COMMAND(tcpcb, db_show_tcpcb)
2039 {
2040 	struct tcpcb *tp;
2041 
2042 	if (!have_addr) {
2043 		db_printf("usage: show tcpcb <addr>\n");
2044 		return;
2045 	}
2046 	tp = (struct tcpcb *)addr;
2047 
2048 	db_print_tcpcb(tp, "tcpcb", 0);
2049 }
2050 #endif
2051