xref: /freebsd/sys/netinet/tcp_usrreq.c (revision d0bd1251350a0564fb20f0044f061f1c6b6079c2)
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 		/*
825 		 * In case of PRUS_NOTREADY, tcp_usr_ready() is responsible
826 		 * for freeing memory.
827 		 */
828 		if (m && (flags & PRUS_NOTREADY) == 0)
829 			m_freem(m);
830 		error = ECONNRESET;
831 		goto out;
832 	}
833 #ifdef INET6
834 	isipv6 = nam && nam->sa_family == AF_INET6;
835 #endif /* INET6 */
836 	tp = intotcpcb(inp);
837 	TCPDEBUG1();
838 	if (control) {
839 		/* TCP doesn't do control messages (rights, creds, etc) */
840 		if (control->m_len) {
841 			m_freem(control);
842 			if (m)
843 				m_freem(m);
844 			error = EINVAL;
845 			goto out;
846 		}
847 		m_freem(control);	/* empty control, just free it */
848 	}
849 	if (!(flags & PRUS_OOB)) {
850 		sbappendstream(&so->so_snd, m, flags);
851 		if (nam && tp->t_state < TCPS_SYN_SENT) {
852 			/*
853 			 * Do implied connect if not yet connected,
854 			 * initialize window to default value, and
855 			 * initialize maxseg/maxopd using peer's cached
856 			 * MSS.
857 			 */
858 #ifdef INET6
859 			if (isipv6)
860 				error = tcp6_connect(tp, nam, td);
861 #endif /* INET6 */
862 #if defined(INET6) && defined(INET)
863 			else
864 #endif
865 #ifdef INET
866 				error = tcp_connect(tp, nam, td);
867 #endif
868 			if (error)
869 				goto out;
870 			tp->snd_wnd = TTCP_CLIENT_SND_WND;
871 			tcp_mss(tp, -1);
872 		}
873 		if (flags & PRUS_EOF) {
874 			/*
875 			 * Close the send side of the connection after
876 			 * the data is sent.
877 			 */
878 			INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
879 			socantsendmore(so);
880 			tcp_usrclosed(tp);
881 		}
882 		if (!(inp->inp_flags & INP_DROPPED) &&
883 		    !(flags & PRUS_NOTREADY)) {
884 			if (flags & PRUS_MORETOCOME)
885 				tp->t_flags |= TF_MORETOCOME;
886 			error = tcp_output(tp);
887 			if (flags & PRUS_MORETOCOME)
888 				tp->t_flags &= ~TF_MORETOCOME;
889 		}
890 	} else {
891 		/*
892 		 * XXXRW: PRUS_EOF not implemented with PRUS_OOB?
893 		 */
894 		SOCKBUF_LOCK(&so->so_snd);
895 		if (sbspace(&so->so_snd) < -512) {
896 			SOCKBUF_UNLOCK(&so->so_snd);
897 			m_freem(m);
898 			error = ENOBUFS;
899 			goto out;
900 		}
901 		/*
902 		 * According to RFC961 (Assigned Protocols),
903 		 * the urgent pointer points to the last octet
904 		 * of urgent data.  We continue, however,
905 		 * to consider it to indicate the first octet
906 		 * of data past the urgent section.
907 		 * Otherwise, snd_up should be one lower.
908 		 */
909 		sbappendstream_locked(&so->so_snd, m, flags);
910 		SOCKBUF_UNLOCK(&so->so_snd);
911 		if (nam && tp->t_state < TCPS_SYN_SENT) {
912 			/*
913 			 * Do implied connect if not yet connected,
914 			 * initialize window to default value, and
915 			 * initialize maxseg/maxopd using peer's cached
916 			 * MSS.
917 			 */
918 #ifdef INET6
919 			if (isipv6)
920 				error = tcp6_connect(tp, nam, td);
921 #endif /* INET6 */
922 #if defined(INET6) && defined(INET)
923 			else
924 #endif
925 #ifdef INET
926 				error = tcp_connect(tp, nam, td);
927 #endif
928 			if (error)
929 				goto out;
930 			tp->snd_wnd = TTCP_CLIENT_SND_WND;
931 			tcp_mss(tp, -1);
932 		}
933 		tp->snd_up = tp->snd_una + sbavail(&so->so_snd);
934 		if (!(flags & PRUS_NOTREADY)) {
935 			tp->t_flags |= TF_FORCEDATA;
936 			error = tcp_output(tp);
937 			tp->t_flags &= ~TF_FORCEDATA;
938 		}
939 	}
940 out:
941 	TCPDEBUG2((flags & PRUS_OOB) ? PRU_SENDOOB :
942 		  ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
943 	INP_WUNLOCK(inp);
944 	if (flags & PRUS_EOF)
945 		INP_INFO_WUNLOCK(&V_tcbinfo);
946 	return (error);
947 }
948 
949 static int
950 tcp_usr_ready(struct socket *so, struct mbuf *m, int count)
951 {
952 	struct inpcb *inp;
953 	struct tcpcb *tp;
954 	int error;
955 
956 	inp = sotoinpcb(so);
957 	INP_WLOCK(inp);
958 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
959 		INP_WUNLOCK(inp);
960 		for (int i = 0; i < count; i++)
961 			m = m_free(m);
962 		return (ECONNRESET);
963 	}
964 	tp = intotcpcb(inp);
965 
966 	SOCKBUF_LOCK(&so->so_snd);
967 	error = sbready(&so->so_snd, m, count);
968 	SOCKBUF_UNLOCK(&so->so_snd);
969 	if (error == 0)
970 		error = tcp_output(tp);
971 	INP_WUNLOCK(inp);
972 
973 	return (error);
974 }
975 
976 /*
977  * Abort the TCP.  Drop the connection abruptly.
978  */
979 static void
980 tcp_usr_abort(struct socket *so)
981 {
982 	struct inpcb *inp;
983 	struct tcpcb *tp = NULL;
984 	TCPDEBUG0;
985 
986 	inp = sotoinpcb(so);
987 	KASSERT(inp != NULL, ("tcp_usr_abort: inp == NULL"));
988 
989 	INP_INFO_WLOCK(&V_tcbinfo);
990 	INP_WLOCK(inp);
991 	KASSERT(inp->inp_socket != NULL,
992 	    ("tcp_usr_abort: inp_socket == NULL"));
993 
994 	/*
995 	 * If we still have full TCP state, and we're not dropped, drop.
996 	 */
997 	if (!(inp->inp_flags & INP_TIMEWAIT) &&
998 	    !(inp->inp_flags & INP_DROPPED)) {
999 		tp = intotcpcb(inp);
1000 		TCPDEBUG1();
1001 		tcp_drop(tp, ECONNABORTED);
1002 		TCPDEBUG2(PRU_ABORT);
1003 	}
1004 	if (!(inp->inp_flags & INP_DROPPED)) {
1005 		SOCK_LOCK(so);
1006 		so->so_state |= SS_PROTOREF;
1007 		SOCK_UNLOCK(so);
1008 		inp->inp_flags |= INP_SOCKREF;
1009 	}
1010 	INP_WUNLOCK(inp);
1011 	INP_INFO_WUNLOCK(&V_tcbinfo);
1012 }
1013 
1014 /*
1015  * TCP socket is closed.  Start friendly disconnect.
1016  */
1017 static void
1018 tcp_usr_close(struct socket *so)
1019 {
1020 	struct inpcb *inp;
1021 	struct tcpcb *tp = NULL;
1022 	TCPDEBUG0;
1023 
1024 	inp = sotoinpcb(so);
1025 	KASSERT(inp != NULL, ("tcp_usr_close: inp == NULL"));
1026 
1027 	INP_INFO_WLOCK(&V_tcbinfo);
1028 	INP_WLOCK(inp);
1029 	KASSERT(inp->inp_socket != NULL,
1030 	    ("tcp_usr_close: inp_socket == NULL"));
1031 
1032 	/*
1033 	 * If we still have full TCP state, and we're not dropped, initiate
1034 	 * a disconnect.
1035 	 */
1036 	if (!(inp->inp_flags & INP_TIMEWAIT) &&
1037 	    !(inp->inp_flags & INP_DROPPED)) {
1038 		tp = intotcpcb(inp);
1039 		TCPDEBUG1();
1040 		tcp_disconnect(tp);
1041 		TCPDEBUG2(PRU_CLOSE);
1042 	}
1043 	if (!(inp->inp_flags & INP_DROPPED)) {
1044 		SOCK_LOCK(so);
1045 		so->so_state |= SS_PROTOREF;
1046 		SOCK_UNLOCK(so);
1047 		inp->inp_flags |= INP_SOCKREF;
1048 	}
1049 	INP_WUNLOCK(inp);
1050 	INP_INFO_WUNLOCK(&V_tcbinfo);
1051 }
1052 
1053 /*
1054  * Receive out-of-band data.
1055  */
1056 static int
1057 tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags)
1058 {
1059 	int error = 0;
1060 	struct inpcb *inp;
1061 	struct tcpcb *tp = NULL;
1062 
1063 	TCPDEBUG0;
1064 	inp = sotoinpcb(so);
1065 	KASSERT(inp != NULL, ("tcp_usr_rcvoob: inp == NULL"));
1066 	INP_WLOCK(inp);
1067 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1068 		error = ECONNRESET;
1069 		goto out;
1070 	}
1071 	tp = intotcpcb(inp);
1072 	TCPDEBUG1();
1073 	if ((so->so_oobmark == 0 &&
1074 	     (so->so_rcv.sb_state & SBS_RCVATMARK) == 0) ||
1075 	    so->so_options & SO_OOBINLINE ||
1076 	    tp->t_oobflags & TCPOOB_HADDATA) {
1077 		error = EINVAL;
1078 		goto out;
1079 	}
1080 	if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
1081 		error = EWOULDBLOCK;
1082 		goto out;
1083 	}
1084 	m->m_len = 1;
1085 	*mtod(m, caddr_t) = tp->t_iobc;
1086 	if ((flags & MSG_PEEK) == 0)
1087 		tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
1088 
1089 out:
1090 	TCPDEBUG2(PRU_RCVOOB);
1091 	INP_WUNLOCK(inp);
1092 	return (error);
1093 }
1094 
1095 #ifdef INET
1096 struct pr_usrreqs tcp_usrreqs = {
1097 	.pru_abort =		tcp_usr_abort,
1098 	.pru_accept =		tcp_usr_accept,
1099 	.pru_attach =		tcp_usr_attach,
1100 	.pru_bind =		tcp_usr_bind,
1101 	.pru_connect =		tcp_usr_connect,
1102 	.pru_control =		in_control,
1103 	.pru_detach =		tcp_usr_detach,
1104 	.pru_disconnect =	tcp_usr_disconnect,
1105 	.pru_listen =		tcp_usr_listen,
1106 	.pru_peeraddr =		in_getpeeraddr,
1107 	.pru_rcvd =		tcp_usr_rcvd,
1108 	.pru_rcvoob =		tcp_usr_rcvoob,
1109 	.pru_send =		tcp_usr_send,
1110 	.pru_ready =		tcp_usr_ready,
1111 	.pru_shutdown =		tcp_usr_shutdown,
1112 	.pru_sockaddr =		in_getsockaddr,
1113 	.pru_sosetlabel =	in_pcbsosetlabel,
1114 	.pru_close =		tcp_usr_close,
1115 };
1116 #endif /* INET */
1117 
1118 #ifdef INET6
1119 struct pr_usrreqs tcp6_usrreqs = {
1120 	.pru_abort =		tcp_usr_abort,
1121 	.pru_accept =		tcp6_usr_accept,
1122 	.pru_attach =		tcp_usr_attach,
1123 	.pru_bind =		tcp6_usr_bind,
1124 	.pru_connect =		tcp6_usr_connect,
1125 	.pru_control =		in6_control,
1126 	.pru_detach =		tcp_usr_detach,
1127 	.pru_disconnect =	tcp_usr_disconnect,
1128 	.pru_listen =		tcp6_usr_listen,
1129 	.pru_peeraddr =		in6_mapped_peeraddr,
1130 	.pru_rcvd =		tcp_usr_rcvd,
1131 	.pru_rcvoob =		tcp_usr_rcvoob,
1132 	.pru_send =		tcp_usr_send,
1133 	.pru_ready =		tcp_usr_ready,
1134 	.pru_shutdown =		tcp_usr_shutdown,
1135 	.pru_sockaddr =		in6_mapped_sockaddr,
1136 	.pru_sosetlabel =	in_pcbsosetlabel,
1137 	.pru_close =		tcp_usr_close,
1138 };
1139 #endif /* INET6 */
1140 
1141 #ifdef INET
1142 /*
1143  * Common subroutine to open a TCP connection to remote host specified
1144  * by struct sockaddr_in in mbuf *nam.  Call in_pcbbind to assign a local
1145  * port number if needed.  Call in_pcbconnect_setup to do the routing and
1146  * to choose a local host address (interface).  If there is an existing
1147  * incarnation of the same connection in TIME-WAIT state and if the remote
1148  * host was sending CC options and if the connection duration was < MSL, then
1149  * truncate the previous TIME-WAIT state and proceed.
1150  * Initialize connection parameters and enter SYN-SENT state.
1151  */
1152 static int
1153 tcp_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1154 {
1155 	struct inpcb *inp = tp->t_inpcb, *oinp;
1156 	struct socket *so = inp->inp_socket;
1157 	struct in_addr laddr;
1158 	u_short lport;
1159 	int error;
1160 
1161 	INP_WLOCK_ASSERT(inp);
1162 	INP_HASH_WLOCK(&V_tcbinfo);
1163 
1164 	if (inp->inp_lport == 0) {
1165 		error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1166 		if (error)
1167 			goto out;
1168 	}
1169 
1170 	/*
1171 	 * Cannot simply call in_pcbconnect, because there might be an
1172 	 * earlier incarnation of this same connection still in
1173 	 * TIME_WAIT state, creating an ADDRINUSE error.
1174 	 */
1175 	laddr = inp->inp_laddr;
1176 	lport = inp->inp_lport;
1177 	error = in_pcbconnect_setup(inp, nam, &laddr.s_addr, &lport,
1178 	    &inp->inp_faddr.s_addr, &inp->inp_fport, &oinp, td->td_ucred);
1179 	if (error && oinp == NULL)
1180 		goto out;
1181 	if (oinp) {
1182 		error = EADDRINUSE;
1183 		goto out;
1184 	}
1185 	inp->inp_laddr = laddr;
1186 	in_pcbrehash(inp);
1187 	INP_HASH_WUNLOCK(&V_tcbinfo);
1188 
1189 	/*
1190 	 * Compute window scaling to request:
1191 	 * Scale to fit into sweet spot.  See tcp_syncache.c.
1192 	 * XXX: This should move to tcp_output().
1193 	 */
1194 	while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1195 	    (TCP_MAXWIN << tp->request_r_scale) < sb_max)
1196 		tp->request_r_scale++;
1197 
1198 	soisconnecting(so);
1199 	TCPSTAT_INC(tcps_connattempt);
1200 	tcp_state_change(tp, TCPS_SYN_SENT);
1201 	tp->iss = tcp_new_isn(tp);
1202 	tcp_sendseqinit(tp);
1203 
1204 	return 0;
1205 
1206 out:
1207 	INP_HASH_WUNLOCK(&V_tcbinfo);
1208 	return (error);
1209 }
1210 #endif /* INET */
1211 
1212 #ifdef INET6
1213 static int
1214 tcp6_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1215 {
1216 	struct inpcb *inp = tp->t_inpcb;
1217 	int error;
1218 
1219 	INP_WLOCK_ASSERT(inp);
1220 	INP_HASH_WLOCK(&V_tcbinfo);
1221 
1222 	if (inp->inp_lport == 0) {
1223 		error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1224 		if (error)
1225 			goto out;
1226 	}
1227 	error = in6_pcbconnect(inp, nam, td->td_ucred);
1228 	if (error != 0)
1229 		goto out;
1230 	INP_HASH_WUNLOCK(&V_tcbinfo);
1231 
1232 	/* Compute window scaling to request.  */
1233 	while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1234 	    (TCP_MAXWIN << tp->request_r_scale) < sb_max)
1235 		tp->request_r_scale++;
1236 
1237 	soisconnecting(inp->inp_socket);
1238 	TCPSTAT_INC(tcps_connattempt);
1239 	tcp_state_change(tp, TCPS_SYN_SENT);
1240 	tp->iss = tcp_new_isn(tp);
1241 	tcp_sendseqinit(tp);
1242 
1243 	return 0;
1244 
1245 out:
1246 	INP_HASH_WUNLOCK(&V_tcbinfo);
1247 	return error;
1248 }
1249 #endif /* INET6 */
1250 
1251 /*
1252  * Export TCP internal state information via a struct tcp_info, based on the
1253  * Linux 2.6 API.  Not ABI compatible as our constants are mapped differently
1254  * (TCP state machine, etc).  We export all information using FreeBSD-native
1255  * constants -- for example, the numeric values for tcpi_state will differ
1256  * from Linux.
1257  */
1258 static void
1259 tcp_fill_info(struct tcpcb *tp, struct tcp_info *ti)
1260 {
1261 
1262 	INP_WLOCK_ASSERT(tp->t_inpcb);
1263 	bzero(ti, sizeof(*ti));
1264 
1265 	ti->tcpi_state = tp->t_state;
1266 	if ((tp->t_flags & TF_REQ_TSTMP) && (tp->t_flags & TF_RCVD_TSTMP))
1267 		ti->tcpi_options |= TCPI_OPT_TIMESTAMPS;
1268 	if (tp->t_flags & TF_SACK_PERMIT)
1269 		ti->tcpi_options |= TCPI_OPT_SACK;
1270 	if ((tp->t_flags & TF_REQ_SCALE) && (tp->t_flags & TF_RCVD_SCALE)) {
1271 		ti->tcpi_options |= TCPI_OPT_WSCALE;
1272 		ti->tcpi_snd_wscale = tp->snd_scale;
1273 		ti->tcpi_rcv_wscale = tp->rcv_scale;
1274 	}
1275 
1276 	ti->tcpi_rto = tp->t_rxtcur * tick;
1277 	ti->tcpi_last_data_recv = (long)(ticks - (int)tp->t_rcvtime) * tick;
1278 	ti->tcpi_rtt = ((u_int64_t)tp->t_srtt * tick) >> TCP_RTT_SHIFT;
1279 	ti->tcpi_rttvar = ((u_int64_t)tp->t_rttvar * tick) >> TCP_RTTVAR_SHIFT;
1280 
1281 	ti->tcpi_snd_ssthresh = tp->snd_ssthresh;
1282 	ti->tcpi_snd_cwnd = tp->snd_cwnd;
1283 
1284 	/*
1285 	 * FreeBSD-specific extension fields for tcp_info.
1286 	 */
1287 	ti->tcpi_rcv_space = tp->rcv_wnd;
1288 	ti->tcpi_rcv_nxt = tp->rcv_nxt;
1289 	ti->tcpi_snd_wnd = tp->snd_wnd;
1290 	ti->tcpi_snd_bwnd = 0;		/* Unused, kept for compat. */
1291 	ti->tcpi_snd_nxt = tp->snd_nxt;
1292 	ti->tcpi_snd_mss = tp->t_maxseg;
1293 	ti->tcpi_rcv_mss = tp->t_maxseg;
1294 	if (tp->t_flags & TF_TOE)
1295 		ti->tcpi_options |= TCPI_OPT_TOE;
1296 	ti->tcpi_snd_rexmitpack = tp->t_sndrexmitpack;
1297 	ti->tcpi_rcv_ooopack = tp->t_rcvoopack;
1298 	ti->tcpi_snd_zerowin = tp->t_sndzerowin;
1299 }
1300 
1301 /*
1302  * tcp_ctloutput() must drop the inpcb lock before performing copyin on
1303  * socket option arguments.  When it re-acquires the lock after the copy, it
1304  * has to revalidate that the connection is still valid for the socket
1305  * option.
1306  */
1307 #define INP_WLOCK_RECHECK(inp) do {					\
1308 	INP_WLOCK(inp);							\
1309 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {		\
1310 		INP_WUNLOCK(inp);					\
1311 		return (ECONNRESET);					\
1312 	}								\
1313 	tp = intotcpcb(inp);						\
1314 } while(0)
1315 
1316 int
1317 tcp_ctloutput(struct socket *so, struct sockopt *sopt)
1318 {
1319 	int	error, opt, optval;
1320 	u_int	ui;
1321 	struct	inpcb *inp;
1322 	struct	tcpcb *tp;
1323 	struct	tcp_info ti;
1324 	char buf[TCP_CA_NAME_MAX];
1325 	struct cc_algo *algo;
1326 
1327 	error = 0;
1328 	inp = sotoinpcb(so);
1329 	KASSERT(inp != NULL, ("tcp_ctloutput: inp == NULL"));
1330 	INP_WLOCK(inp);
1331 	if (sopt->sopt_level != IPPROTO_TCP) {
1332 #ifdef INET6
1333 		if (inp->inp_vflag & INP_IPV6PROTO) {
1334 			INP_WUNLOCK(inp);
1335 			error = ip6_ctloutput(so, sopt);
1336 		}
1337 #endif /* INET6 */
1338 #if defined(INET6) && defined(INET)
1339 		else
1340 #endif
1341 #ifdef INET
1342 		{
1343 			INP_WUNLOCK(inp);
1344 			error = ip_ctloutput(so, sopt);
1345 		}
1346 #endif
1347 		return (error);
1348 	}
1349 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
1350 		INP_WUNLOCK(inp);
1351 		return (ECONNRESET);
1352 	}
1353 
1354 	switch (sopt->sopt_dir) {
1355 	case SOPT_SET:
1356 		switch (sopt->sopt_name) {
1357 #ifdef TCP_SIGNATURE
1358 		case TCP_MD5SIG:
1359 			INP_WUNLOCK(inp);
1360 			error = sooptcopyin(sopt, &optval, sizeof optval,
1361 			    sizeof optval);
1362 			if (error)
1363 				return (error);
1364 
1365 			INP_WLOCK_RECHECK(inp);
1366 			if (optval > 0)
1367 				tp->t_flags |= TF_SIGNATURE;
1368 			else
1369 				tp->t_flags &= ~TF_SIGNATURE;
1370 			goto unlock_and_done;
1371 #endif /* TCP_SIGNATURE */
1372 
1373 		case TCP_NODELAY:
1374 		case TCP_NOOPT:
1375 			INP_WUNLOCK(inp);
1376 			error = sooptcopyin(sopt, &optval, sizeof optval,
1377 			    sizeof optval);
1378 			if (error)
1379 				return (error);
1380 
1381 			INP_WLOCK_RECHECK(inp);
1382 			switch (sopt->sopt_name) {
1383 			case TCP_NODELAY:
1384 				opt = TF_NODELAY;
1385 				break;
1386 			case TCP_NOOPT:
1387 				opt = TF_NOOPT;
1388 				break;
1389 			default:
1390 				opt = 0; /* dead code to fool gcc */
1391 				break;
1392 			}
1393 
1394 			if (optval)
1395 				tp->t_flags |= opt;
1396 			else
1397 				tp->t_flags &= ~opt;
1398 unlock_and_done:
1399 #ifdef TCP_OFFLOAD
1400 			if (tp->t_flags & TF_TOE) {
1401 				tcp_offload_ctloutput(tp, sopt->sopt_dir,
1402 				    sopt->sopt_name);
1403 			}
1404 #endif
1405 			INP_WUNLOCK(inp);
1406 			break;
1407 
1408 		case TCP_NOPUSH:
1409 			INP_WUNLOCK(inp);
1410 			error = sooptcopyin(sopt, &optval, sizeof optval,
1411 			    sizeof optval);
1412 			if (error)
1413 				return (error);
1414 
1415 			INP_WLOCK_RECHECK(inp);
1416 			if (optval)
1417 				tp->t_flags |= TF_NOPUSH;
1418 			else if (tp->t_flags & TF_NOPUSH) {
1419 				tp->t_flags &= ~TF_NOPUSH;
1420 				if (TCPS_HAVEESTABLISHED(tp->t_state))
1421 					error = tcp_output(tp);
1422 			}
1423 			goto unlock_and_done;
1424 
1425 		case TCP_MAXSEG:
1426 			INP_WUNLOCK(inp);
1427 			error = sooptcopyin(sopt, &optval, sizeof optval,
1428 			    sizeof optval);
1429 			if (error)
1430 				return (error);
1431 
1432 			INP_WLOCK_RECHECK(inp);
1433 			if (optval > 0 && optval <= tp->t_maxseg &&
1434 			    optval + 40 >= V_tcp_minmss)
1435 				tp->t_maxseg = optval;
1436 			else
1437 				error = EINVAL;
1438 			goto unlock_and_done;
1439 
1440 		case TCP_INFO:
1441 			INP_WUNLOCK(inp);
1442 			error = EINVAL;
1443 			break;
1444 
1445 		case TCP_CONGESTION:
1446 			INP_WUNLOCK(inp);
1447 			bzero(buf, sizeof(buf));
1448 			error = sooptcopyin(sopt, &buf, sizeof(buf), 1);
1449 			if (error)
1450 				break;
1451 			INP_WLOCK_RECHECK(inp);
1452 			/*
1453 			 * Return EINVAL if we can't find the requested cc algo.
1454 			 */
1455 			error = EINVAL;
1456 			CC_LIST_RLOCK();
1457 			STAILQ_FOREACH(algo, &cc_list, entries) {
1458 				if (strncmp(buf, algo->name, TCP_CA_NAME_MAX)
1459 				    == 0) {
1460 					/* We've found the requested algo. */
1461 					error = 0;
1462 					/*
1463 					 * We hold a write lock over the tcb
1464 					 * so it's safe to do these things
1465 					 * without ordering concerns.
1466 					 */
1467 					if (CC_ALGO(tp)->cb_destroy != NULL)
1468 						CC_ALGO(tp)->cb_destroy(tp->ccv);
1469 					CC_ALGO(tp) = algo;
1470 					/*
1471 					 * If something goes pear shaped
1472 					 * initialising the new algo,
1473 					 * fall back to newreno (which
1474 					 * does not require initialisation).
1475 					 */
1476 					if (algo->cb_init != NULL)
1477 						if (algo->cb_init(tp->ccv) > 0) {
1478 							CC_ALGO(tp) = &newreno_cc_algo;
1479 							/*
1480 							 * The only reason init
1481 							 * should fail is
1482 							 * because of malloc.
1483 							 */
1484 							error = ENOMEM;
1485 						}
1486 					break; /* Break the STAILQ_FOREACH. */
1487 				}
1488 			}
1489 			CC_LIST_RUNLOCK();
1490 			goto unlock_and_done;
1491 
1492 		case TCP_KEEPIDLE:
1493 		case TCP_KEEPINTVL:
1494 		case TCP_KEEPINIT:
1495 			INP_WUNLOCK(inp);
1496 			error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui));
1497 			if (error)
1498 				return (error);
1499 
1500 			if (ui > (UINT_MAX / hz)) {
1501 				error = EINVAL;
1502 				break;
1503 			}
1504 			ui *= hz;
1505 
1506 			INP_WLOCK_RECHECK(inp);
1507 			switch (sopt->sopt_name) {
1508 			case TCP_KEEPIDLE:
1509 				tp->t_keepidle = ui;
1510 				/*
1511 				 * XXX: better check current remaining
1512 				 * timeout and "merge" it with new value.
1513 				 */
1514 				if ((tp->t_state > TCPS_LISTEN) &&
1515 				    (tp->t_state <= TCPS_CLOSING))
1516 					tcp_timer_activate(tp, TT_KEEP,
1517 					    TP_KEEPIDLE(tp));
1518 				break;
1519 			case TCP_KEEPINTVL:
1520 				tp->t_keepintvl = ui;
1521 				if ((tp->t_state == TCPS_FIN_WAIT_2) &&
1522 				    (TP_MAXIDLE(tp) > 0))
1523 					tcp_timer_activate(tp, TT_2MSL,
1524 					    TP_MAXIDLE(tp));
1525 				break;
1526 			case TCP_KEEPINIT:
1527 				tp->t_keepinit = ui;
1528 				if (tp->t_state == TCPS_SYN_RECEIVED ||
1529 				    tp->t_state == TCPS_SYN_SENT)
1530 					tcp_timer_activate(tp, TT_KEEP,
1531 					    TP_KEEPINIT(tp));
1532 				break;
1533 			}
1534 			goto unlock_and_done;
1535 
1536 		case TCP_KEEPCNT:
1537 			INP_WUNLOCK(inp);
1538 			error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui));
1539 			if (error)
1540 				return (error);
1541 
1542 			INP_WLOCK_RECHECK(inp);
1543 			tp->t_keepcnt = ui;
1544 			if ((tp->t_state == TCPS_FIN_WAIT_2) &&
1545 			    (TP_MAXIDLE(tp) > 0))
1546 				tcp_timer_activate(tp, TT_2MSL,
1547 				    TP_MAXIDLE(tp));
1548 			goto unlock_and_done;
1549 
1550 		default:
1551 			INP_WUNLOCK(inp);
1552 			error = ENOPROTOOPT;
1553 			break;
1554 		}
1555 		break;
1556 
1557 	case SOPT_GET:
1558 		tp = intotcpcb(inp);
1559 		switch (sopt->sopt_name) {
1560 #ifdef TCP_SIGNATURE
1561 		case TCP_MD5SIG:
1562 			optval = (tp->t_flags & TF_SIGNATURE) ? 1 : 0;
1563 			INP_WUNLOCK(inp);
1564 			error = sooptcopyout(sopt, &optval, sizeof optval);
1565 			break;
1566 #endif
1567 
1568 		case TCP_NODELAY:
1569 			optval = tp->t_flags & TF_NODELAY;
1570 			INP_WUNLOCK(inp);
1571 			error = sooptcopyout(sopt, &optval, sizeof optval);
1572 			break;
1573 		case TCP_MAXSEG:
1574 			optval = tp->t_maxseg;
1575 			INP_WUNLOCK(inp);
1576 			error = sooptcopyout(sopt, &optval, sizeof optval);
1577 			break;
1578 		case TCP_NOOPT:
1579 			optval = tp->t_flags & TF_NOOPT;
1580 			INP_WUNLOCK(inp);
1581 			error = sooptcopyout(sopt, &optval, sizeof optval);
1582 			break;
1583 		case TCP_NOPUSH:
1584 			optval = tp->t_flags & TF_NOPUSH;
1585 			INP_WUNLOCK(inp);
1586 			error = sooptcopyout(sopt, &optval, sizeof optval);
1587 			break;
1588 		case TCP_INFO:
1589 			tcp_fill_info(tp, &ti);
1590 			INP_WUNLOCK(inp);
1591 			error = sooptcopyout(sopt, &ti, sizeof ti);
1592 			break;
1593 		case TCP_CONGESTION:
1594 			bzero(buf, sizeof(buf));
1595 			strlcpy(buf, CC_ALGO(tp)->name, TCP_CA_NAME_MAX);
1596 			INP_WUNLOCK(inp);
1597 			error = sooptcopyout(sopt, buf, TCP_CA_NAME_MAX);
1598 			break;
1599 		case TCP_KEEPIDLE:
1600 		case TCP_KEEPINTVL:
1601 		case TCP_KEEPINIT:
1602 		case TCP_KEEPCNT:
1603 			switch (sopt->sopt_name) {
1604 			case TCP_KEEPIDLE:
1605 				ui = tp->t_keepidle / hz;
1606 				break;
1607 			case TCP_KEEPINTVL:
1608 				ui = tp->t_keepintvl / hz;
1609 				break;
1610 			case TCP_KEEPINIT:
1611 				ui = tp->t_keepinit / hz;
1612 				break;
1613 			case TCP_KEEPCNT:
1614 				ui = tp->t_keepcnt;
1615 				break;
1616 			}
1617 			INP_WUNLOCK(inp);
1618 			error = sooptcopyout(sopt, &ui, sizeof(ui));
1619 			break;
1620 		default:
1621 			INP_WUNLOCK(inp);
1622 			error = ENOPROTOOPT;
1623 			break;
1624 		}
1625 		break;
1626 	}
1627 	return (error);
1628 }
1629 #undef INP_WLOCK_RECHECK
1630 
1631 /*
1632  * Attach TCP protocol to socket, allocating
1633  * internet protocol control block, tcp control block,
1634  * bufer space, and entering LISTEN state if to accept connections.
1635  */
1636 static int
1637 tcp_attach(struct socket *so)
1638 {
1639 	struct tcpcb *tp;
1640 	struct inpcb *inp;
1641 	int error;
1642 
1643 	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
1644 		error = soreserve(so, V_tcp_sendspace, V_tcp_recvspace);
1645 		if (error)
1646 			return (error);
1647 	}
1648 	so->so_rcv.sb_flags |= SB_AUTOSIZE;
1649 	so->so_snd.sb_flags |= SB_AUTOSIZE;
1650 	INP_INFO_WLOCK(&V_tcbinfo);
1651 	error = in_pcballoc(so, &V_tcbinfo);
1652 	if (error) {
1653 		INP_INFO_WUNLOCK(&V_tcbinfo);
1654 		return (error);
1655 	}
1656 	inp = sotoinpcb(so);
1657 #ifdef INET6
1658 	if (inp->inp_vflag & INP_IPV6PROTO) {
1659 		inp->inp_vflag |= INP_IPV6;
1660 		inp->in6p_hops = -1;	/* use kernel default */
1661 	}
1662 	else
1663 #endif
1664 	inp->inp_vflag |= INP_IPV4;
1665 	tp = tcp_newtcpcb(inp);
1666 	if (tp == NULL) {
1667 		in_pcbdetach(inp);
1668 		in_pcbfree(inp);
1669 		INP_INFO_WUNLOCK(&V_tcbinfo);
1670 		return (ENOBUFS);
1671 	}
1672 	tp->t_state = TCPS_CLOSED;
1673 	INP_WUNLOCK(inp);
1674 	INP_INFO_WUNLOCK(&V_tcbinfo);
1675 	return (0);
1676 }
1677 
1678 /*
1679  * Initiate (or continue) disconnect.
1680  * If embryonic state, just send reset (once).
1681  * If in ``let data drain'' option and linger null, just drop.
1682  * Otherwise (hard), mark socket disconnecting and drop
1683  * current input data; switch states based on user close, and
1684  * send segment to peer (with FIN).
1685  */
1686 static void
1687 tcp_disconnect(struct tcpcb *tp)
1688 {
1689 	struct inpcb *inp = tp->t_inpcb;
1690 	struct socket *so = inp->inp_socket;
1691 
1692 	INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
1693 	INP_WLOCK_ASSERT(inp);
1694 
1695 	/*
1696 	 * Neither tcp_close() nor tcp_drop() should return NULL, as the
1697 	 * socket is still open.
1698 	 */
1699 	if (tp->t_state < TCPS_ESTABLISHED) {
1700 		tp = tcp_close(tp);
1701 		KASSERT(tp != NULL,
1702 		    ("tcp_disconnect: tcp_close() returned NULL"));
1703 	} else if ((so->so_options & SO_LINGER) && so->so_linger == 0) {
1704 		tp = tcp_drop(tp, 0);
1705 		KASSERT(tp != NULL,
1706 		    ("tcp_disconnect: tcp_drop() returned NULL"));
1707 	} else {
1708 		soisdisconnecting(so);
1709 		sbflush(&so->so_rcv);
1710 		tcp_usrclosed(tp);
1711 		if (!(inp->inp_flags & INP_DROPPED))
1712 			tcp_output(tp);
1713 	}
1714 }
1715 
1716 /*
1717  * User issued close, and wish to trail through shutdown states:
1718  * if never received SYN, just forget it.  If got a SYN from peer,
1719  * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
1720  * If already got a FIN from peer, then almost done; go to LAST_ACK
1721  * state.  In all other cases, have already sent FIN to peer (e.g.
1722  * after PRU_SHUTDOWN), and just have to play tedious game waiting
1723  * for peer to send FIN or not respond to keep-alives, etc.
1724  * We can let the user exit from the close as soon as the FIN is acked.
1725  */
1726 static void
1727 tcp_usrclosed(struct tcpcb *tp)
1728 {
1729 
1730 	INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
1731 	INP_WLOCK_ASSERT(tp->t_inpcb);
1732 
1733 	switch (tp->t_state) {
1734 	case TCPS_LISTEN:
1735 #ifdef TCP_OFFLOAD
1736 		tcp_offload_listen_stop(tp);
1737 #endif
1738 		/* FALLTHROUGH */
1739 	case TCPS_CLOSED:
1740 		tcp_state_change(tp, TCPS_CLOSED);
1741 		tp = tcp_close(tp);
1742 		/*
1743 		 * tcp_close() should never return NULL here as the socket is
1744 		 * still open.
1745 		 */
1746 		KASSERT(tp != NULL,
1747 		    ("tcp_usrclosed: tcp_close() returned NULL"));
1748 		break;
1749 
1750 	case TCPS_SYN_SENT:
1751 	case TCPS_SYN_RECEIVED:
1752 		tp->t_flags |= TF_NEEDFIN;
1753 		break;
1754 
1755 	case TCPS_ESTABLISHED:
1756 		tcp_state_change(tp, TCPS_FIN_WAIT_1);
1757 		break;
1758 
1759 	case TCPS_CLOSE_WAIT:
1760 		tcp_state_change(tp, TCPS_LAST_ACK);
1761 		break;
1762 	}
1763 	if (tp->t_state >= TCPS_FIN_WAIT_2) {
1764 		soisdisconnected(tp->t_inpcb->inp_socket);
1765 		/* Prevent the connection hanging in FIN_WAIT_2 forever. */
1766 		if (tp->t_state == TCPS_FIN_WAIT_2) {
1767 			int timeout;
1768 
1769 			timeout = (tcp_fast_finwait2_recycle) ?
1770 			    tcp_finwait2_timeout : TP_MAXIDLE(tp);
1771 			tcp_timer_activate(tp, TT_2MSL, timeout);
1772 		}
1773 	}
1774 }
1775 
1776 #ifdef DDB
1777 static void
1778 db_print_indent(int indent)
1779 {
1780 	int i;
1781 
1782 	for (i = 0; i < indent; i++)
1783 		db_printf(" ");
1784 }
1785 
1786 static void
1787 db_print_tstate(int t_state)
1788 {
1789 
1790 	switch (t_state) {
1791 	case TCPS_CLOSED:
1792 		db_printf("TCPS_CLOSED");
1793 		return;
1794 
1795 	case TCPS_LISTEN:
1796 		db_printf("TCPS_LISTEN");
1797 		return;
1798 
1799 	case TCPS_SYN_SENT:
1800 		db_printf("TCPS_SYN_SENT");
1801 		return;
1802 
1803 	case TCPS_SYN_RECEIVED:
1804 		db_printf("TCPS_SYN_RECEIVED");
1805 		return;
1806 
1807 	case TCPS_ESTABLISHED:
1808 		db_printf("TCPS_ESTABLISHED");
1809 		return;
1810 
1811 	case TCPS_CLOSE_WAIT:
1812 		db_printf("TCPS_CLOSE_WAIT");
1813 		return;
1814 
1815 	case TCPS_FIN_WAIT_1:
1816 		db_printf("TCPS_FIN_WAIT_1");
1817 		return;
1818 
1819 	case TCPS_CLOSING:
1820 		db_printf("TCPS_CLOSING");
1821 		return;
1822 
1823 	case TCPS_LAST_ACK:
1824 		db_printf("TCPS_LAST_ACK");
1825 		return;
1826 
1827 	case TCPS_FIN_WAIT_2:
1828 		db_printf("TCPS_FIN_WAIT_2");
1829 		return;
1830 
1831 	case TCPS_TIME_WAIT:
1832 		db_printf("TCPS_TIME_WAIT");
1833 		return;
1834 
1835 	default:
1836 		db_printf("unknown");
1837 		return;
1838 	}
1839 }
1840 
1841 static void
1842 db_print_tflags(u_int t_flags)
1843 {
1844 	int comma;
1845 
1846 	comma = 0;
1847 	if (t_flags & TF_ACKNOW) {
1848 		db_printf("%sTF_ACKNOW", comma ? ", " : "");
1849 		comma = 1;
1850 	}
1851 	if (t_flags & TF_DELACK) {
1852 		db_printf("%sTF_DELACK", comma ? ", " : "");
1853 		comma = 1;
1854 	}
1855 	if (t_flags & TF_NODELAY) {
1856 		db_printf("%sTF_NODELAY", comma ? ", " : "");
1857 		comma = 1;
1858 	}
1859 	if (t_flags & TF_NOOPT) {
1860 		db_printf("%sTF_NOOPT", comma ? ", " : "");
1861 		comma = 1;
1862 	}
1863 	if (t_flags & TF_SENTFIN) {
1864 		db_printf("%sTF_SENTFIN", comma ? ", " : "");
1865 		comma = 1;
1866 	}
1867 	if (t_flags & TF_REQ_SCALE) {
1868 		db_printf("%sTF_REQ_SCALE", comma ? ", " : "");
1869 		comma = 1;
1870 	}
1871 	if (t_flags & TF_RCVD_SCALE) {
1872 		db_printf("%sTF_RECVD_SCALE", comma ? ", " : "");
1873 		comma = 1;
1874 	}
1875 	if (t_flags & TF_REQ_TSTMP) {
1876 		db_printf("%sTF_REQ_TSTMP", comma ? ", " : "");
1877 		comma = 1;
1878 	}
1879 	if (t_flags & TF_RCVD_TSTMP) {
1880 		db_printf("%sTF_RCVD_TSTMP", comma ? ", " : "");
1881 		comma = 1;
1882 	}
1883 	if (t_flags & TF_SACK_PERMIT) {
1884 		db_printf("%sTF_SACK_PERMIT", comma ? ", " : "");
1885 		comma = 1;
1886 	}
1887 	if (t_flags & TF_NEEDSYN) {
1888 		db_printf("%sTF_NEEDSYN", comma ? ", " : "");
1889 		comma = 1;
1890 	}
1891 	if (t_flags & TF_NEEDFIN) {
1892 		db_printf("%sTF_NEEDFIN", comma ? ", " : "");
1893 		comma = 1;
1894 	}
1895 	if (t_flags & TF_NOPUSH) {
1896 		db_printf("%sTF_NOPUSH", comma ? ", " : "");
1897 		comma = 1;
1898 	}
1899 	if (t_flags & TF_MORETOCOME) {
1900 		db_printf("%sTF_MORETOCOME", comma ? ", " : "");
1901 		comma = 1;
1902 	}
1903 	if (t_flags & TF_LQ_OVERFLOW) {
1904 		db_printf("%sTF_LQ_OVERFLOW", comma ? ", " : "");
1905 		comma = 1;
1906 	}
1907 	if (t_flags & TF_LASTIDLE) {
1908 		db_printf("%sTF_LASTIDLE", comma ? ", " : "");
1909 		comma = 1;
1910 	}
1911 	if (t_flags & TF_RXWIN0SENT) {
1912 		db_printf("%sTF_RXWIN0SENT", comma ? ", " : "");
1913 		comma = 1;
1914 	}
1915 	if (t_flags & TF_FASTRECOVERY) {
1916 		db_printf("%sTF_FASTRECOVERY", comma ? ", " : "");
1917 		comma = 1;
1918 	}
1919 	if (t_flags & TF_CONGRECOVERY) {
1920 		db_printf("%sTF_CONGRECOVERY", comma ? ", " : "");
1921 		comma = 1;
1922 	}
1923 	if (t_flags & TF_WASFRECOVERY) {
1924 		db_printf("%sTF_WASFRECOVERY", comma ? ", " : "");
1925 		comma = 1;
1926 	}
1927 	if (t_flags & TF_SIGNATURE) {
1928 		db_printf("%sTF_SIGNATURE", comma ? ", " : "");
1929 		comma = 1;
1930 	}
1931 	if (t_flags & TF_FORCEDATA) {
1932 		db_printf("%sTF_FORCEDATA", comma ? ", " : "");
1933 		comma = 1;
1934 	}
1935 	if (t_flags & TF_TSO) {
1936 		db_printf("%sTF_TSO", comma ? ", " : "");
1937 		comma = 1;
1938 	}
1939 	if (t_flags & TF_ECN_PERMIT) {
1940 		db_printf("%sTF_ECN_PERMIT", comma ? ", " : "");
1941 		comma = 1;
1942 	}
1943 }
1944 
1945 static void
1946 db_print_toobflags(char t_oobflags)
1947 {
1948 	int comma;
1949 
1950 	comma = 0;
1951 	if (t_oobflags & TCPOOB_HAVEDATA) {
1952 		db_printf("%sTCPOOB_HAVEDATA", comma ? ", " : "");
1953 		comma = 1;
1954 	}
1955 	if (t_oobflags & TCPOOB_HADDATA) {
1956 		db_printf("%sTCPOOB_HADDATA", comma ? ", " : "");
1957 		comma = 1;
1958 	}
1959 }
1960 
1961 static void
1962 db_print_tcpcb(struct tcpcb *tp, const char *name, int indent)
1963 {
1964 
1965 	db_print_indent(indent);
1966 	db_printf("%s at %p\n", name, tp);
1967 
1968 	indent += 2;
1969 
1970 	db_print_indent(indent);
1971 	db_printf("t_segq first: %p   t_segqlen: %d   t_dupacks: %d\n",
1972 	   tp->t_segq, tp->t_segqlen, tp->t_dupacks);
1973 
1974 	db_print_indent(indent);
1975 	db_printf("tt_rexmt: %p   tt_persist: %p   tt_keep: %p\n",
1976 	    &tp->t_timers->tt_rexmt, &tp->t_timers->tt_persist, &tp->t_timers->tt_keep);
1977 
1978 	db_print_indent(indent);
1979 	db_printf("tt_2msl: %p   tt_delack: %p   t_inpcb: %p\n", &tp->t_timers->tt_2msl,
1980 	    &tp->t_timers->tt_delack, tp->t_inpcb);
1981 
1982 	db_print_indent(indent);
1983 	db_printf("t_state: %d (", tp->t_state);
1984 	db_print_tstate(tp->t_state);
1985 	db_printf(")\n");
1986 
1987 	db_print_indent(indent);
1988 	db_printf("t_flags: 0x%x (", tp->t_flags);
1989 	db_print_tflags(tp->t_flags);
1990 	db_printf(")\n");
1991 
1992 	db_print_indent(indent);
1993 	db_printf("snd_una: 0x%08x   snd_max: 0x%08x   snd_nxt: x0%08x\n",
1994 	    tp->snd_una, tp->snd_max, tp->snd_nxt);
1995 
1996 	db_print_indent(indent);
1997 	db_printf("snd_up: 0x%08x   snd_wl1: 0x%08x   snd_wl2: 0x%08x\n",
1998 	   tp->snd_up, tp->snd_wl1, tp->snd_wl2);
1999 
2000 	db_print_indent(indent);
2001 	db_printf("iss: 0x%08x   irs: 0x%08x   rcv_nxt: 0x%08x\n",
2002 	    tp->iss, tp->irs, tp->rcv_nxt);
2003 
2004 	db_print_indent(indent);
2005 	db_printf("rcv_adv: 0x%08x   rcv_wnd: %lu   rcv_up: 0x%08x\n",
2006 	    tp->rcv_adv, tp->rcv_wnd, tp->rcv_up);
2007 
2008 	db_print_indent(indent);
2009 	db_printf("snd_wnd: %lu   snd_cwnd: %lu\n",
2010 	   tp->snd_wnd, tp->snd_cwnd);
2011 
2012 	db_print_indent(indent);
2013 	db_printf("snd_ssthresh: %lu   snd_recover: "
2014 	    "0x%08x\n", tp->snd_ssthresh, tp->snd_recover);
2015 
2016 	db_print_indent(indent);
2017 	db_printf("t_maxopd: %u   t_rcvtime: %u   t_startime: %u\n",
2018 	    tp->t_maxopd, tp->t_rcvtime, tp->t_starttime);
2019 
2020 	db_print_indent(indent);
2021 	db_printf("t_rttime: %u   t_rtsq: 0x%08x\n",
2022 	    tp->t_rtttime, tp->t_rtseq);
2023 
2024 	db_print_indent(indent);
2025 	db_printf("t_rxtcur: %d   t_maxseg: %u   t_srtt: %d\n",
2026 	    tp->t_rxtcur, tp->t_maxseg, tp->t_srtt);
2027 
2028 	db_print_indent(indent);
2029 	db_printf("t_rttvar: %d   t_rxtshift: %d   t_rttmin: %u   "
2030 	    "t_rttbest: %u\n", tp->t_rttvar, tp->t_rxtshift, tp->t_rttmin,
2031 	    tp->t_rttbest);
2032 
2033 	db_print_indent(indent);
2034 	db_printf("t_rttupdated: %lu   max_sndwnd: %lu   t_softerror: %d\n",
2035 	    tp->t_rttupdated, tp->max_sndwnd, tp->t_softerror);
2036 
2037 	db_print_indent(indent);
2038 	db_printf("t_oobflags: 0x%x (", tp->t_oobflags);
2039 	db_print_toobflags(tp->t_oobflags);
2040 	db_printf(")   t_iobc: 0x%02x\n", tp->t_iobc);
2041 
2042 	db_print_indent(indent);
2043 	db_printf("snd_scale: %u   rcv_scale: %u   request_r_scale: %u\n",
2044 	    tp->snd_scale, tp->rcv_scale, tp->request_r_scale);
2045 
2046 	db_print_indent(indent);
2047 	db_printf("ts_recent: %u   ts_recent_age: %u\n",
2048 	    tp->ts_recent, tp->ts_recent_age);
2049 
2050 	db_print_indent(indent);
2051 	db_printf("ts_offset: %u   last_ack_sent: 0x%08x   snd_cwnd_prev: "
2052 	    "%lu\n", tp->ts_offset, tp->last_ack_sent, tp->snd_cwnd_prev);
2053 
2054 	db_print_indent(indent);
2055 	db_printf("snd_ssthresh_prev: %lu   snd_recover_prev: 0x%08x   "
2056 	    "t_badrxtwin: %u\n", tp->snd_ssthresh_prev,
2057 	    tp->snd_recover_prev, tp->t_badrxtwin);
2058 
2059 	db_print_indent(indent);
2060 	db_printf("snd_numholes: %d  snd_holes first: %p\n",
2061 	    tp->snd_numholes, TAILQ_FIRST(&tp->snd_holes));
2062 
2063 	db_print_indent(indent);
2064 	db_printf("snd_fack: 0x%08x   rcv_numsacks: %d   sack_newdata: "
2065 	    "0x%08x\n", tp->snd_fack, tp->rcv_numsacks, tp->sack_newdata);
2066 
2067 	/* Skip sackblks, sackhint. */
2068 
2069 	db_print_indent(indent);
2070 	db_printf("t_rttlow: %d   rfbuf_ts: %u   rfbuf_cnt: %d\n",
2071 	    tp->t_rttlow, tp->rfbuf_ts, tp->rfbuf_cnt);
2072 }
2073 
2074 DB_SHOW_COMMAND(tcpcb, db_show_tcpcb)
2075 {
2076 	struct tcpcb *tp;
2077 
2078 	if (!have_addr) {
2079 		db_printf("usage: show tcpcb <addr>\n");
2080 		return;
2081 	}
2082 	tp = (struct tcpcb *)addr;
2083 
2084 	db_print_tcpcb(tp, "tcpcb", 0);
2085 }
2086 #endif
2087