xref: /freebsd/sys/netinet/tcp_usrreq.c (revision f0a75d274af375d15b97b830966b99a02b7db911)
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  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 4. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	From: @(#)tcp_usrreq.c	8.2 (Berkeley) 1/3/94
32  * $FreeBSD$
33  */
34 
35 #include "opt_ddb.h"
36 #include "opt_inet.h"
37 #include "opt_inet6.h"
38 #include "opt_tcpdebug.h"
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/malloc.h>
43 #include <sys/kernel.h>
44 #include <sys/sysctl.h>
45 #include <sys/mbuf.h>
46 #ifdef INET6
47 #include <sys/domain.h>
48 #endif /* INET6 */
49 #include <sys/socket.h>
50 #include <sys/socketvar.h>
51 #include <sys/protosw.h>
52 #include <sys/proc.h>
53 #include <sys/jail.h>
54 
55 #ifdef DDB
56 #include <ddb/ddb.h>
57 #endif
58 
59 #include <net/if.h>
60 #include <net/route.h>
61 
62 #include <netinet/in.h>
63 #include <netinet/in_systm.h>
64 #ifdef INET6
65 #include <netinet/ip6.h>
66 #endif
67 #include <netinet/in_pcb.h>
68 #ifdef INET6
69 #include <netinet6/in6_pcb.h>
70 #endif
71 #include <netinet/in_var.h>
72 #include <netinet/ip_var.h>
73 #ifdef INET6
74 #include <netinet6/ip6_var.h>
75 #include <netinet6/scope6_var.h>
76 #endif
77 #include <netinet/tcp.h>
78 #include <netinet/tcp_fsm.h>
79 #include <netinet/tcp_seq.h>
80 #include <netinet/tcp_timer.h>
81 #include <netinet/tcp_var.h>
82 #include <netinet/tcpip.h>
83 #ifdef TCPDEBUG
84 #include <netinet/tcp_debug.h>
85 #endif
86 
87 /*
88  * TCP protocol interface to socket abstraction.
89  */
90 extern	char *tcpstates[];	/* XXX ??? */
91 
92 static int	tcp_attach(struct socket *);
93 static int	tcp_connect(struct tcpcb *, struct sockaddr *,
94 		    struct thread *td);
95 #ifdef INET6
96 static int	tcp6_connect(struct tcpcb *, struct sockaddr *,
97 		    struct thread *td);
98 #endif /* INET6 */
99 static void	tcp_disconnect(struct tcpcb *);
100 static void	tcp_usrclosed(struct tcpcb *);
101 static void	tcp_fill_info(struct tcpcb *, struct tcp_info *);
102 
103 #ifdef TCPDEBUG
104 #define	TCPDEBUG0	int ostate = 0
105 #define	TCPDEBUG1()	ostate = tp ? tp->t_state : 0
106 #define	TCPDEBUG2(req)	if (tp && (so->so_options & SO_DEBUG)) \
107 				tcp_trace(TA_USER, ostate, tp, 0, 0, req)
108 #else
109 #define	TCPDEBUG0
110 #define	TCPDEBUG1()
111 #define	TCPDEBUG2(req)
112 #endif
113 
114 /*
115  * TCP attaches to socket via pru_attach(), reserving space,
116  * and an internet control block.
117  */
118 static int
119 tcp_usr_attach(struct socket *so, int proto, struct thread *td)
120 {
121 	struct inpcb *inp;
122 	struct tcpcb *tp = NULL;
123 	int error;
124 	TCPDEBUG0;
125 
126 	inp = sotoinpcb(so);
127 	KASSERT(inp == NULL, ("tcp_usr_attach: inp != NULL"));
128 	TCPDEBUG1();
129 
130 	error = tcp_attach(so);
131 	if (error)
132 		goto out;
133 
134 	if ((so->so_options & SO_LINGER) && so->so_linger == 0)
135 		so->so_linger = TCP_LINGERTIME;
136 
137 	inp = sotoinpcb(so);
138 	tp = intotcpcb(inp);
139 out:
140 	TCPDEBUG2(PRU_ATTACH);
141 	return error;
142 }
143 
144 /*
145  * tcp_detach is called when the socket layer loses its final reference
146  * to the socket, be it a file descriptor reference, a reference from TCP,
147  * etc.  At this point, there is only one case in which we will keep around
148  * inpcb state: time wait.
149  *
150  * This function can probably be re-absorbed back into tcp_usr_detach() now
151  * that there is a single detach path.
152  */
153 static void
154 tcp_detach(struct socket *so, struct inpcb *inp)
155 {
156 	struct tcpcb *tp;
157 #ifdef INET6
158 	int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6) != 0;
159 #endif
160 
161 	INP_INFO_WLOCK_ASSERT(&tcbinfo);
162 	INP_LOCK_ASSERT(inp);
163 
164 	KASSERT(so->so_pcb == inp, ("tcp_detach: so_pcb != inp"));
165 	KASSERT(inp->inp_socket == so, ("tcp_detach: inp_socket != so"));
166 
167 	tp = intotcpcb(inp);
168 
169 	if (inp->inp_vflag & INP_TIMEWAIT) {
170 		/*
171 		 * There are two cases to handle: one in which the time wait
172 		 * state is being discarded (INP_DROPPED), and one in which
173 		 * this connection will remain in timewait.  In the former,
174 		 * it is time to discard all state (except tcptw, which has
175 		 * already been discarded by the timewait close code, which
176 		 * should be further up the call stack somewhere).  In the
177 		 * latter case, we detach from the socket, but leave the pcb
178 		 * present until timewait ends.
179 		 *
180 		 * XXXRW: Would it be cleaner to free the tcptw here?
181 		 */
182 		if (inp->inp_vflag & INP_DROPPED) {
183 			KASSERT(tp == NULL, ("tcp_detach: INP_TIMEWAIT && "
184 			    "INP_DROPPED && tp != NULL"));
185 #ifdef INET6
186 			if (isipv6) {
187 				in6_pcbdetach(inp);
188 				in6_pcbfree(inp);
189 			} else {
190 #endif
191 				in_pcbdetach(inp);
192 				in_pcbfree(inp);
193 #ifdef INET6
194 			}
195 #endif
196 		} else {
197 #ifdef INET6
198 			if (isipv6)
199 				in6_pcbdetach(inp);
200 			else
201 #endif
202 				in_pcbdetach(inp);
203 			INP_UNLOCK(inp);
204 		}
205 	} else {
206 		/*
207 		 * If the connection is not in timewait, we consider two
208 		 * two conditions: one in which no further processing is
209 		 * necessary (dropped || embryonic), and one in which TCP is
210 		 * not yet done, but no longer requires the socket, so the
211 		 * pcb will persist for the time being.
212 		 *
213 		 * XXXRW: Does the second case still occur?
214 		 */
215 		if (inp->inp_vflag & INP_DROPPED ||
216 		    tp->t_state < TCPS_SYN_SENT) {
217 			tcp_discardcb(tp);
218 #ifdef INET6
219 			if (isipv6) {
220 				in6_pcbdetach(inp);
221 				in6_pcbfree(inp);
222 			} else {
223 #endif
224 				in_pcbdetach(inp);
225 				in_pcbfree(inp);
226 #ifdef INET6
227 			}
228 #endif
229 		} else {
230 #ifdef INET6
231 			if (isipv6)
232 				in6_pcbdetach(inp);
233 			else
234 #endif
235 				in_pcbdetach(inp);
236 		}
237 	}
238 }
239 
240 /*
241  * pru_detach() detaches the TCP protocol from the socket.
242  * If the protocol state is non-embryonic, then can't
243  * do this directly: have to initiate a pru_disconnect(),
244  * which may finish later; embryonic TCB's can just
245  * be discarded here.
246  */
247 static void
248 tcp_usr_detach(struct socket *so)
249 {
250 	struct inpcb *inp;
251 	struct tcpcb *tp;
252 	TCPDEBUG0;
253 
254 	inp = sotoinpcb(so);
255 	KASSERT(inp != NULL, ("tcp_usr_detach: inp == NULL"));
256 	INP_INFO_WLOCK(&tcbinfo);
257 	INP_LOCK(inp);
258 	KASSERT(inp->inp_socket != NULL,
259 	    ("tcp_usr_detach: inp_socket == NULL"));
260 	TCPDEBUG1();
261 
262 	tcp_detach(so, inp);
263 	tp = NULL;
264 	TCPDEBUG2(PRU_DETACH);
265 	INP_INFO_WUNLOCK(&tcbinfo);
266 }
267 
268 /*
269  * Give the socket an address.
270  */
271 static int
272 tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
273 {
274 	int error = 0;
275 	struct inpcb *inp;
276 	struct tcpcb *tp = NULL;
277 	struct sockaddr_in *sinp;
278 
279 	sinp = (struct sockaddr_in *)nam;
280 	if (nam->sa_len != sizeof (*sinp))
281 		return (EINVAL);
282 	/*
283 	 * Must check for multicast addresses and disallow binding
284 	 * to them.
285 	 */
286 	if (sinp->sin_family == AF_INET &&
287 	    IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
288 		return (EAFNOSUPPORT);
289 
290 	TCPDEBUG0;
291 	INP_INFO_WLOCK(&tcbinfo);
292 	inp = sotoinpcb(so);
293 	KASSERT(inp != NULL, ("tcp_usr_bind: inp == NULL"));
294 	INP_LOCK(inp);
295 	if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
296 		error = EINVAL;
297 		goto out;
298 	}
299 	tp = intotcpcb(inp);
300 	TCPDEBUG1();
301 	error = in_pcbbind(inp, nam, td->td_ucred);
302 out:
303 	TCPDEBUG2(PRU_BIND);
304 	INP_UNLOCK(inp);
305 	INP_INFO_WUNLOCK(&tcbinfo);
306 
307 	return (error);
308 }
309 
310 #ifdef INET6
311 static int
312 tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
313 {
314 	int error = 0;
315 	struct inpcb *inp;
316 	struct tcpcb *tp = NULL;
317 	struct sockaddr_in6 *sin6p;
318 
319 	sin6p = (struct sockaddr_in6 *)nam;
320 	if (nam->sa_len != sizeof (*sin6p))
321 		return (EINVAL);
322 	/*
323 	 * Must check for multicast addresses and disallow binding
324 	 * to them.
325 	 */
326 	if (sin6p->sin6_family == AF_INET6 &&
327 	    IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr))
328 		return (EAFNOSUPPORT);
329 
330 	TCPDEBUG0;
331 	INP_INFO_WLOCK(&tcbinfo);
332 	inp = sotoinpcb(so);
333 	KASSERT(inp != NULL, ("tcp6_usr_bind: inp == NULL"));
334 	INP_LOCK(inp);
335 	if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
336 		error = EINVAL;
337 		goto out;
338 	}
339 	tp = intotcpcb(inp);
340 	TCPDEBUG1();
341 	inp->inp_vflag &= ~INP_IPV4;
342 	inp->inp_vflag |= INP_IPV6;
343 	if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
344 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6p->sin6_addr))
345 			inp->inp_vflag |= INP_IPV4;
346 		else if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
347 			struct sockaddr_in sin;
348 
349 			in6_sin6_2_sin(&sin, sin6p);
350 			inp->inp_vflag |= INP_IPV4;
351 			inp->inp_vflag &= ~INP_IPV6;
352 			error = in_pcbbind(inp, (struct sockaddr *)&sin,
353 			    td->td_ucred);
354 			goto out;
355 		}
356 	}
357 	error = in6_pcbbind(inp, nam, td->td_ucred);
358 out:
359 	TCPDEBUG2(PRU_BIND);
360 	INP_UNLOCK(inp);
361 	INP_INFO_WUNLOCK(&tcbinfo);
362 	return (error);
363 }
364 #endif /* INET6 */
365 
366 /*
367  * Prepare to accept connections.
368  */
369 static int
370 tcp_usr_listen(struct socket *so, int backlog, struct thread *td)
371 {
372 	int error = 0;
373 	struct inpcb *inp;
374 	struct tcpcb *tp = NULL;
375 
376 	TCPDEBUG0;
377 	INP_INFO_WLOCK(&tcbinfo);
378 	inp = sotoinpcb(so);
379 	KASSERT(inp != NULL, ("tcp_usr_listen: inp == NULL"));
380 	INP_LOCK(inp);
381 	if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
382 		error = EINVAL;
383 		goto out;
384 	}
385 	tp = intotcpcb(inp);
386 	TCPDEBUG1();
387 	SOCK_LOCK(so);
388 	error = solisten_proto_check(so);
389 	if (error == 0 && inp->inp_lport == 0)
390 		error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
391 	if (error == 0) {
392 		tp->t_state = TCPS_LISTEN;
393 		solisten_proto(so, backlog);
394 	}
395 	SOCK_UNLOCK(so);
396 
397 out:
398 	TCPDEBUG2(PRU_LISTEN);
399 	INP_UNLOCK(inp);
400 	INP_INFO_WUNLOCK(&tcbinfo);
401 	return (error);
402 }
403 
404 #ifdef INET6
405 static int
406 tcp6_usr_listen(struct socket *so, int backlog, struct thread *td)
407 {
408 	int error = 0;
409 	struct inpcb *inp;
410 	struct tcpcb *tp = NULL;
411 
412 	TCPDEBUG0;
413 	INP_INFO_WLOCK(&tcbinfo);
414 	inp = sotoinpcb(so);
415 	KASSERT(inp != NULL, ("tcp6_usr_listen: inp == NULL"));
416 	INP_LOCK(inp);
417 	if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
418 		error = EINVAL;
419 		goto out;
420 	}
421 	tp = intotcpcb(inp);
422 	TCPDEBUG1();
423 	SOCK_LOCK(so);
424 	error = solisten_proto_check(so);
425 	if (error == 0 && inp->inp_lport == 0) {
426 		inp->inp_vflag &= ~INP_IPV4;
427 		if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
428 			inp->inp_vflag |= INP_IPV4;
429 		error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
430 	}
431 	if (error == 0) {
432 		tp->t_state = TCPS_LISTEN;
433 		solisten_proto(so, backlog);
434 	}
435 	SOCK_UNLOCK(so);
436 
437 out:
438 	TCPDEBUG2(PRU_LISTEN);
439 	INP_UNLOCK(inp);
440 	INP_INFO_WUNLOCK(&tcbinfo);
441 	return (error);
442 }
443 #endif /* INET6 */
444 
445 /*
446  * Initiate connection to peer.
447  * Create a template for use in transmissions on this connection.
448  * Enter SYN_SENT state, and mark socket as connecting.
449  * Start keep-alive timer, and seed output sequence space.
450  * Send initial segment on connection.
451  */
452 static int
453 tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
454 {
455 	int error = 0;
456 	struct inpcb *inp;
457 	struct tcpcb *tp = NULL;
458 	struct sockaddr_in *sinp;
459 
460 	sinp = (struct sockaddr_in *)nam;
461 	if (nam->sa_len != sizeof (*sinp))
462 		return (EINVAL);
463 	/*
464 	 * Must disallow TCP ``connections'' to multicast addresses.
465 	 */
466 	if (sinp->sin_family == AF_INET
467 	    && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
468 		return (EAFNOSUPPORT);
469 	if (jailed(td->td_ucred))
470 		prison_remote_ip(td->td_ucred, 0, &sinp->sin_addr.s_addr);
471 
472 	TCPDEBUG0;
473 	INP_INFO_WLOCK(&tcbinfo);
474 	inp = sotoinpcb(so);
475 	KASSERT(inp != NULL, ("tcp_usr_connect: inp == NULL"));
476 	INP_LOCK(inp);
477 	if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
478 		error = EINVAL;
479 		goto out;
480 	}
481 	tp = intotcpcb(inp);
482 	TCPDEBUG1();
483 	if ((error = tcp_connect(tp, nam, td)) != 0)
484 		goto out;
485 	error = tcp_output(tp);
486 out:
487 	TCPDEBUG2(PRU_CONNECT);
488 	INP_UNLOCK(inp);
489 	INP_INFO_WUNLOCK(&tcbinfo);
490 	return (error);
491 }
492 
493 #ifdef INET6
494 static int
495 tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
496 {
497 	int error = 0;
498 	struct inpcb *inp;
499 	struct tcpcb *tp = NULL;
500 	struct sockaddr_in6 *sin6p;
501 
502 	TCPDEBUG0;
503 
504 	sin6p = (struct sockaddr_in6 *)nam;
505 	if (nam->sa_len != sizeof (*sin6p))
506 		return (EINVAL);
507 	/*
508 	 * Must disallow TCP ``connections'' to multicast addresses.
509 	 */
510 	if (sin6p->sin6_family == AF_INET6
511 	    && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr))
512 		return (EAFNOSUPPORT);
513 
514 	INP_INFO_WLOCK(&tcbinfo);
515 	inp = sotoinpcb(so);
516 	KASSERT(inp != NULL, ("tcp6_usr_connect: inp == NULL"));
517 	INP_LOCK(inp);
518 	if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
519 		error = EINVAL;
520 		goto out;
521 	}
522 	tp = intotcpcb(inp);
523 	TCPDEBUG1();
524 	if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
525 		struct sockaddr_in sin;
526 
527 		if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
528 			error = EINVAL;
529 			goto out;
530 		}
531 
532 		in6_sin6_2_sin(&sin, sin6p);
533 		inp->inp_vflag |= INP_IPV4;
534 		inp->inp_vflag &= ~INP_IPV6;
535 		if ((error = tcp_connect(tp, (struct sockaddr *)&sin, td)) != 0)
536 			goto out;
537 		error = tcp_output(tp);
538 		goto out;
539 	}
540 	inp->inp_vflag &= ~INP_IPV4;
541 	inp->inp_vflag |= INP_IPV6;
542 	inp->inp_inc.inc_isipv6 = 1;
543 	if ((error = tcp6_connect(tp, nam, td)) != 0)
544 		goto out;
545 	error = tcp_output(tp);
546 
547 out:
548 	TCPDEBUG2(PRU_CONNECT);
549 	INP_UNLOCK(inp);
550 	INP_INFO_WUNLOCK(&tcbinfo);
551 	return (error);
552 }
553 #endif /* INET6 */
554 
555 /*
556  * Initiate disconnect from peer.
557  * If connection never passed embryonic stage, just drop;
558  * else if don't need to let data drain, then can just drop anyways,
559  * else have to begin TCP shutdown process: mark socket disconnecting,
560  * drain unread data, state switch to reflect user close, and
561  * send segment (e.g. FIN) to peer.  Socket will be really disconnected
562  * when peer sends FIN and acks ours.
563  *
564  * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.
565  */
566 static int
567 tcp_usr_disconnect(struct socket *so)
568 {
569 	struct inpcb *inp;
570 	struct tcpcb *tp = NULL;
571 	int error = 0;
572 
573 	TCPDEBUG0;
574 	INP_INFO_WLOCK(&tcbinfo);
575 	inp = sotoinpcb(so);
576 	KASSERT(inp != NULL, ("tcp_usr_disconnect: inp == NULL"));
577 	INP_LOCK(inp);
578 	if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
579 		error = ECONNRESET;
580 		goto out;
581 	}
582 	tp = intotcpcb(inp);
583 	TCPDEBUG1();
584 	tcp_disconnect(tp);
585 out:
586 	TCPDEBUG2(PRU_DISCONNECT);
587 	INP_UNLOCK(inp);
588 	INP_INFO_WUNLOCK(&tcbinfo);
589 	return (error);
590 }
591 
592 /*
593  * Accept a connection.  Essentially all the work is
594  * done at higher levels; just return the address
595  * of the peer, storing through addr.
596  */
597 static int
598 tcp_usr_accept(struct socket *so, struct sockaddr **nam)
599 {
600 	int error = 0;
601 	struct inpcb *inp = NULL;
602 	struct tcpcb *tp = NULL;
603 	struct in_addr addr;
604 	in_port_t port = 0;
605 	TCPDEBUG0;
606 
607 	if (so->so_state & SS_ISDISCONNECTED)
608 		return (ECONNABORTED);
609 
610 	inp = sotoinpcb(so);
611 	KASSERT(inp != NULL, ("tcp_usr_accept: inp == NULL"));
612 	INP_LOCK(inp);
613 	if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
614 		error = ECONNABORTED;
615 		goto out;
616 	}
617 	tp = intotcpcb(inp);
618 	TCPDEBUG1();
619 
620 	/*
621 	 * We inline in_setpeeraddr and COMMON_END here, so that we can
622 	 * copy the data of interest and defer the malloc until after we
623 	 * release the lock.
624 	 */
625 	port = inp->inp_fport;
626 	addr = inp->inp_faddr;
627 
628 out:
629 	TCPDEBUG2(PRU_ACCEPT);
630 	INP_UNLOCK(inp);
631 	if (error == 0)
632 		*nam = in_sockaddr(port, &addr);
633 	return error;
634 }
635 
636 #ifdef INET6
637 static int
638 tcp6_usr_accept(struct socket *so, struct sockaddr **nam)
639 {
640 	struct inpcb *inp = NULL;
641 	int error = 0;
642 	struct tcpcb *tp = NULL;
643 	struct in_addr addr;
644 	struct in6_addr addr6;
645 	in_port_t port = 0;
646 	int v4 = 0;
647 	TCPDEBUG0;
648 
649 	if (so->so_state & SS_ISDISCONNECTED)
650 		return (ECONNABORTED);
651 
652 	inp = sotoinpcb(so);
653 	KASSERT(inp != NULL, ("tcp6_usr_accept: inp == NULL"));
654 	INP_LOCK(inp);
655 	if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
656 		error = ECONNABORTED;
657 		goto out;
658 	}
659 	tp = intotcpcb(inp);
660 	TCPDEBUG1();
661 
662 	/*
663 	 * We inline in6_mapped_peeraddr and COMMON_END here, so that we can
664 	 * copy the data of interest and defer the malloc until after we
665 	 * release the lock.
666 	 */
667 	if (inp->inp_vflag & INP_IPV4) {
668 		v4 = 1;
669 		port = inp->inp_fport;
670 		addr = inp->inp_faddr;
671 	} else {
672 		port = inp->inp_fport;
673 		addr6 = inp->in6p_faddr;
674 	}
675 
676 out:
677 	TCPDEBUG2(PRU_ACCEPT);
678 	INP_UNLOCK(inp);
679 	if (error == 0) {
680 		if (v4)
681 			*nam = in6_v4mapsin6_sockaddr(port, &addr);
682 		else
683 			*nam = in6_sockaddr(port, &addr6);
684 	}
685 	return error;
686 }
687 #endif /* INET6 */
688 
689 /*
690  * This is the wrapper function for in_setsockaddr. We just pass down
691  * the pcbinfo for in_setsockaddr to lock. We don't want to do the locking
692  * here because in_setsockaddr will call malloc and can block.
693  */
694 static int
695 tcp_sockaddr(struct socket *so, struct sockaddr **nam)
696 {
697 	return (in_setsockaddr(so, nam, &tcbinfo));
698 }
699 
700 /*
701  * This is the wrapper function for in_setpeeraddr. We just pass down
702  * the pcbinfo for in_setpeeraddr to lock.
703  */
704 static int
705 tcp_peeraddr(struct socket *so, struct sockaddr **nam)
706 {
707 	return (in_setpeeraddr(so, nam, &tcbinfo));
708 }
709 
710 /*
711  * Mark the connection as being incapable of further output.
712  */
713 static int
714 tcp_usr_shutdown(struct socket *so)
715 {
716 	int error = 0;
717 	struct inpcb *inp;
718 	struct tcpcb *tp = NULL;
719 
720 	TCPDEBUG0;
721 	INP_INFO_WLOCK(&tcbinfo);
722 	inp = sotoinpcb(so);
723 	KASSERT(inp != NULL, ("inp == NULL"));
724 	INP_LOCK(inp);
725 	if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
726 		error = ECONNRESET;
727 		goto out;
728 	}
729 	tp = intotcpcb(inp);
730 	TCPDEBUG1();
731 	socantsendmore(so);
732 	tcp_usrclosed(tp);
733 	error = tcp_output(tp);
734 
735 out:
736 	TCPDEBUG2(PRU_SHUTDOWN);
737 	INP_UNLOCK(inp);
738 	INP_INFO_WUNLOCK(&tcbinfo);
739 
740 	return (error);
741 }
742 
743 /*
744  * After a receive, possibly send window update to peer.
745  */
746 static int
747 tcp_usr_rcvd(struct socket *so, int flags)
748 {
749 	struct inpcb *inp;
750 	struct tcpcb *tp = NULL;
751 	int error = 0;
752 
753 	TCPDEBUG0;
754 	inp = sotoinpcb(so);
755 	KASSERT(inp != NULL, ("tcp_usr_rcvd: inp == NULL"));
756 	INP_LOCK(inp);
757 	if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
758 		error = ECONNRESET;
759 		goto out;
760 	}
761 	tp = intotcpcb(inp);
762 	TCPDEBUG1();
763 	tcp_output(tp);
764 
765 out:
766 	TCPDEBUG2(PRU_RCVD);
767 	INP_UNLOCK(inp);
768 	return (error);
769 }
770 
771 /*
772  * Do a send by putting data in output queue and updating urgent
773  * marker if URG set.  Possibly send more data.  Unlike the other
774  * pru_*() routines, the mbuf chains are our responsibility.  We
775  * must either enqueue them or free them.  The other pru_* routines
776  * generally are caller-frees.
777  */
778 static int
779 tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
780     struct sockaddr *nam, struct mbuf *control, struct thread *td)
781 {
782 	int error = 0;
783 	struct inpcb *inp;
784 	struct tcpcb *tp = NULL;
785 	int headlocked = 0;
786 #ifdef INET6
787 	int isipv6;
788 #endif
789 	TCPDEBUG0;
790 
791 	/*
792 	 * We require the pcbinfo lock in two cases:
793 	 *
794 	 * (1) An implied connect is taking place, which can result in
795 	 *     binding IPs and ports and hence modification of the pcb hash
796 	 *     chains.
797 	 *
798 	 * (2) PRUS_EOF is set, resulting in explicit close on the send.
799 	 */
800 	if ((nam != NULL) || (flags & PRUS_EOF)) {
801 		INP_INFO_WLOCK(&tcbinfo);
802 		headlocked = 1;
803 	}
804 	inp = sotoinpcb(so);
805 	KASSERT(inp != NULL, ("tcp_usr_send: inp == NULL"));
806 	INP_LOCK(inp);
807 	if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
808 		if (control)
809 			m_freem(control);
810 		if (m)
811 			m_freem(m);
812 		error = ECONNRESET;
813 		goto out;
814 	}
815 #ifdef INET6
816 	isipv6 = nam && nam->sa_family == AF_INET6;
817 #endif /* INET6 */
818 	tp = intotcpcb(inp);
819 	TCPDEBUG1();
820 	if (control) {
821 		/* TCP doesn't do control messages (rights, creds, etc) */
822 		if (control->m_len) {
823 			m_freem(control);
824 			if (m)
825 				m_freem(m);
826 			error = EINVAL;
827 			goto out;
828 		}
829 		m_freem(control);	/* empty control, just free it */
830 	}
831 	if (!(flags & PRUS_OOB)) {
832 		sbappendstream(&so->so_snd, m);
833 		if (nam && tp->t_state < TCPS_SYN_SENT) {
834 			/*
835 			 * Do implied connect if not yet connected,
836 			 * initialize window to default value, and
837 			 * initialize maxseg/maxopd using peer's cached
838 			 * MSS.
839 			 */
840 			INP_INFO_WLOCK_ASSERT(&tcbinfo);
841 #ifdef INET6
842 			if (isipv6)
843 				error = tcp6_connect(tp, nam, td);
844 			else
845 #endif /* INET6 */
846 			error = tcp_connect(tp, nam, td);
847 			if (error)
848 				goto out;
849 			tp->snd_wnd = TTCP_CLIENT_SND_WND;
850 			tcp_mss(tp, -1);
851 		}
852 		if (flags & PRUS_EOF) {
853 			/*
854 			 * Close the send side of the connection after
855 			 * the data is sent.
856 			 */
857 			INP_INFO_WLOCK_ASSERT(&tcbinfo);
858 			socantsendmore(so);
859 			tcp_usrclosed(tp);
860 		}
861 		if (headlocked) {
862 			INP_INFO_WUNLOCK(&tcbinfo);
863 			headlocked = 0;
864 		}
865 		if (tp != NULL) {
866 			if (flags & PRUS_MORETOCOME)
867 				tp->t_flags |= TF_MORETOCOME;
868 			error = tcp_output(tp);
869 			if (flags & PRUS_MORETOCOME)
870 				tp->t_flags &= ~TF_MORETOCOME;
871 		}
872 	} else {
873 		/*
874 		 * XXXRW: PRUS_EOF not implemented with PRUS_OOB?
875 		 */
876 		SOCKBUF_LOCK(&so->so_snd);
877 		if (sbspace(&so->so_snd) < -512) {
878 			SOCKBUF_UNLOCK(&so->so_snd);
879 			m_freem(m);
880 			error = ENOBUFS;
881 			goto out;
882 		}
883 		/*
884 		 * According to RFC961 (Assigned Protocols),
885 		 * the urgent pointer points to the last octet
886 		 * of urgent data.  We continue, however,
887 		 * to consider it to indicate the first octet
888 		 * of data past the urgent section.
889 		 * Otherwise, snd_up should be one lower.
890 		 */
891 		sbappendstream_locked(&so->so_snd, m);
892 		SOCKBUF_UNLOCK(&so->so_snd);
893 		if (nam && tp->t_state < TCPS_SYN_SENT) {
894 			/*
895 			 * Do implied connect if not yet connected,
896 			 * initialize window to default value, and
897 			 * initialize maxseg/maxopd using peer's cached
898 			 * MSS.
899 			 */
900 			INP_INFO_WLOCK_ASSERT(&tcbinfo);
901 #ifdef INET6
902 			if (isipv6)
903 				error = tcp6_connect(tp, nam, td);
904 			else
905 #endif /* INET6 */
906 			error = tcp_connect(tp, nam, td);
907 			if (error)
908 				goto out;
909 			tp->snd_wnd = TTCP_CLIENT_SND_WND;
910 			tcp_mss(tp, -1);
911 			INP_INFO_WUNLOCK(&tcbinfo);
912 			headlocked = 0;
913 		} else if (nam) {
914 			INP_INFO_WUNLOCK(&tcbinfo);
915 			headlocked = 0;
916 		}
917 		tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
918 		tp->t_flags |= TF_FORCEDATA;
919 		error = tcp_output(tp);
920 		tp->t_flags &= ~TF_FORCEDATA;
921 	}
922 out:
923 	TCPDEBUG2((flags & PRUS_OOB) ? PRU_SENDOOB :
924 		  ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
925 	INP_UNLOCK(inp);
926 	if (headlocked)
927 		INP_INFO_WUNLOCK(&tcbinfo);
928 	return (error);
929 }
930 
931 /*
932  * Abort the TCP.  Drop the connection abruptly.
933  */
934 static void
935 tcp_usr_abort(struct socket *so)
936 {
937 	struct inpcb *inp;
938 	struct tcpcb *tp = NULL;
939 	TCPDEBUG0;
940 
941 	inp = sotoinpcb(so);
942 	KASSERT(inp != NULL, ("tcp_usr_abort: inp == NULL"));
943 
944 	INP_INFO_WLOCK(&tcbinfo);
945 	INP_LOCK(inp);
946 	KASSERT(inp->inp_socket != NULL,
947 	    ("tcp_usr_abort: inp_socket == NULL"));
948 
949 	/*
950 	 * If we still have full TCP state, and we're not dropped, drop.
951 	 */
952 	if (!(inp->inp_vflag & INP_TIMEWAIT) &&
953 	    !(inp->inp_vflag & INP_DROPPED)) {
954 		tp = intotcpcb(inp);
955 		TCPDEBUG1();
956 		tcp_drop(tp, ECONNABORTED);
957 		TCPDEBUG2(PRU_ABORT);
958 	}
959 	if (!(inp->inp_vflag & INP_DROPPED)) {
960 		SOCK_LOCK(so);
961 		so->so_state |= SS_PROTOREF;
962 		SOCK_UNLOCK(so);
963 		inp->inp_vflag |= INP_SOCKREF;
964 	}
965 	INP_UNLOCK(inp);
966 	INP_INFO_WUNLOCK(&tcbinfo);
967 }
968 
969 /*
970  * TCP socket is closed.  Start friendly disconnect.
971  */
972 static void
973 tcp_usr_close(struct socket *so)
974 {
975 	struct inpcb *inp;
976 	struct tcpcb *tp = NULL;
977 	TCPDEBUG0;
978 
979 	inp = sotoinpcb(so);
980 	KASSERT(inp != NULL, ("tcp_usr_close: inp == NULL"));
981 
982 	INP_INFO_WLOCK(&tcbinfo);
983 	INP_LOCK(inp);
984 	KASSERT(inp->inp_socket != NULL,
985 	    ("tcp_usr_close: inp_socket == NULL"));
986 
987 	/*
988 	 * If we still have full TCP state, and we're not dropped, initiate
989 	 * a disconnect.
990 	 */
991 	if (!(inp->inp_vflag & INP_TIMEWAIT) &&
992 	    !(inp->inp_vflag & INP_DROPPED)) {
993 		tp = intotcpcb(inp);
994 		TCPDEBUG1();
995 		tcp_disconnect(tp);
996 		TCPDEBUG2(PRU_CLOSE);
997 	}
998 	if (!(inp->inp_vflag & INP_DROPPED)) {
999 		SOCK_LOCK(so);
1000 		so->so_state |= SS_PROTOREF;
1001 		SOCK_UNLOCK(so);
1002 		inp->inp_vflag |= INP_SOCKREF;
1003 	}
1004 	INP_UNLOCK(inp);
1005 	INP_INFO_WUNLOCK(&tcbinfo);
1006 }
1007 
1008 /*
1009  * Receive out-of-band data.
1010  */
1011 static int
1012 tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags)
1013 {
1014 	int error = 0;
1015 	struct inpcb *inp;
1016 	struct tcpcb *tp = NULL;
1017 
1018 	TCPDEBUG0;
1019 	inp = sotoinpcb(so);
1020 	KASSERT(inp != NULL, ("tcp_usr_rcvoob: inp == NULL"));
1021 	INP_LOCK(inp);
1022 	if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
1023 		error = ECONNRESET;
1024 		goto out;
1025 	}
1026 	tp = intotcpcb(inp);
1027 	TCPDEBUG1();
1028 	if ((so->so_oobmark == 0 &&
1029 	     (so->so_rcv.sb_state & SBS_RCVATMARK) == 0) ||
1030 	    so->so_options & SO_OOBINLINE ||
1031 	    tp->t_oobflags & TCPOOB_HADDATA) {
1032 		error = EINVAL;
1033 		goto out;
1034 	}
1035 	if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
1036 		error = EWOULDBLOCK;
1037 		goto out;
1038 	}
1039 	m->m_len = 1;
1040 	*mtod(m, caddr_t) = tp->t_iobc;
1041 	if ((flags & MSG_PEEK) == 0)
1042 		tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
1043 
1044 out:
1045 	TCPDEBUG2(PRU_RCVOOB);
1046 	INP_UNLOCK(inp);
1047 	return (error);
1048 }
1049 
1050 struct pr_usrreqs tcp_usrreqs = {
1051 	.pru_abort =		tcp_usr_abort,
1052 	.pru_accept =		tcp_usr_accept,
1053 	.pru_attach =		tcp_usr_attach,
1054 	.pru_bind =		tcp_usr_bind,
1055 	.pru_connect =		tcp_usr_connect,
1056 	.pru_control =		in_control,
1057 	.pru_detach =		tcp_usr_detach,
1058 	.pru_disconnect =	tcp_usr_disconnect,
1059 	.pru_listen =		tcp_usr_listen,
1060 	.pru_peeraddr =		tcp_peeraddr,
1061 	.pru_rcvd =		tcp_usr_rcvd,
1062 	.pru_rcvoob =		tcp_usr_rcvoob,
1063 	.pru_send =		tcp_usr_send,
1064 	.pru_shutdown =		tcp_usr_shutdown,
1065 	.pru_sockaddr =		tcp_sockaddr,
1066 	.pru_sosetlabel =	in_pcbsosetlabel,
1067 	.pru_close =		tcp_usr_close,
1068 };
1069 
1070 #ifdef INET6
1071 struct pr_usrreqs tcp6_usrreqs = {
1072 	.pru_abort =		tcp_usr_abort,
1073 	.pru_accept =		tcp6_usr_accept,
1074 	.pru_attach =		tcp_usr_attach,
1075 	.pru_bind =		tcp6_usr_bind,
1076 	.pru_connect =		tcp6_usr_connect,
1077 	.pru_control =		in6_control,
1078 	.pru_detach =		tcp_usr_detach,
1079 	.pru_disconnect =	tcp_usr_disconnect,
1080 	.pru_listen =		tcp6_usr_listen,
1081 	.pru_peeraddr =		in6_mapped_peeraddr,
1082 	.pru_rcvd =		tcp_usr_rcvd,
1083 	.pru_rcvoob =		tcp_usr_rcvoob,
1084 	.pru_send =		tcp_usr_send,
1085 	.pru_shutdown =		tcp_usr_shutdown,
1086 	.pru_sockaddr =		in6_mapped_sockaddr,
1087  	.pru_sosetlabel =	in_pcbsosetlabel,
1088 	.pru_close =		tcp_usr_close,
1089 };
1090 #endif /* INET6 */
1091 
1092 /*
1093  * Common subroutine to open a TCP connection to remote host specified
1094  * by struct sockaddr_in in mbuf *nam.  Call in_pcbbind to assign a local
1095  * port number if needed.  Call in_pcbconnect_setup to do the routing and
1096  * to choose a local host address (interface).  If there is an existing
1097  * incarnation of the same connection in TIME-WAIT state and if the remote
1098  * host was sending CC options and if the connection duration was < MSL, then
1099  * truncate the previous TIME-WAIT state and proceed.
1100  * Initialize connection parameters and enter SYN-SENT state.
1101  */
1102 static int
1103 tcp_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1104 {
1105 	struct inpcb *inp = tp->t_inpcb, *oinp;
1106 	struct socket *so = inp->inp_socket;
1107 	struct in_addr laddr;
1108 	u_short lport;
1109 	int error;
1110 
1111 	INP_INFO_WLOCK_ASSERT(&tcbinfo);
1112 	INP_LOCK_ASSERT(inp);
1113 
1114 	if (inp->inp_lport == 0) {
1115 		error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1116 		if (error)
1117 			return error;
1118 	}
1119 
1120 	/*
1121 	 * Cannot simply call in_pcbconnect, because there might be an
1122 	 * earlier incarnation of this same connection still in
1123 	 * TIME_WAIT state, creating an ADDRINUSE error.
1124 	 */
1125 	laddr = inp->inp_laddr;
1126 	lport = inp->inp_lport;
1127 	error = in_pcbconnect_setup(inp, nam, &laddr.s_addr, &lport,
1128 	    &inp->inp_faddr.s_addr, &inp->inp_fport, &oinp, td->td_ucred);
1129 	if (error && oinp == NULL)
1130 		return error;
1131 	if (oinp)
1132 		return EADDRINUSE;
1133 	inp->inp_laddr = laddr;
1134 	in_pcbrehash(inp);
1135 
1136 	/*
1137 	 * Compute window scaling to request:
1138 	 * Scale to fit into sweet spot.  See tcp_syncache.c.
1139 	 * XXX: This should move to tcp_output().
1140 	 * XXX: This should be based on the actual MSS.
1141 	 */
1142 	while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1143 	    (0x1 << tp->request_r_scale) < tcp_minmss)
1144 		tp->request_r_scale++;
1145 
1146 	soisconnecting(so);
1147 	tcpstat.tcps_connattempt++;
1148 	tp->t_state = TCPS_SYN_SENT;
1149 	callout_reset(tp->tt_keep, tcp_keepinit, tcp_timer_keep, tp);
1150 	tp->iss = tcp_new_isn(tp);
1151 	tp->t_bw_rtseq = tp->iss;
1152 	tcp_sendseqinit(tp);
1153 
1154 	return 0;
1155 }
1156 
1157 #ifdef INET6
1158 static int
1159 tcp6_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1160 {
1161 	struct inpcb *inp = tp->t_inpcb, *oinp;
1162 	struct socket *so = inp->inp_socket;
1163 	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
1164 	struct in6_addr *addr6;
1165 	int error;
1166 
1167 	INP_INFO_WLOCK_ASSERT(&tcbinfo);
1168 	INP_LOCK_ASSERT(inp);
1169 
1170 	if (inp->inp_lport == 0) {
1171 		error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1172 		if (error)
1173 			return error;
1174 	}
1175 
1176 	/*
1177 	 * Cannot simply call in_pcbconnect, because there might be an
1178 	 * earlier incarnation of this same connection still in
1179 	 * TIME_WAIT state, creating an ADDRINUSE error.
1180 	 * in6_pcbladdr() also handles scope zone IDs.
1181 	 */
1182 	error = in6_pcbladdr(inp, nam, &addr6);
1183 	if (error)
1184 		return error;
1185 	oinp = in6_pcblookup_hash(inp->inp_pcbinfo,
1186 				  &sin6->sin6_addr, sin6->sin6_port,
1187 				  IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)
1188 				  ? addr6
1189 				  : &inp->in6p_laddr,
1190 				  inp->inp_lport,  0, NULL);
1191 	if (oinp)
1192 		return EADDRINUSE;
1193 	if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr))
1194 		inp->in6p_laddr = *addr6;
1195 	inp->in6p_faddr = sin6->sin6_addr;
1196 	inp->inp_fport = sin6->sin6_port;
1197 	/* update flowinfo - draft-itojun-ipv6-flowlabel-api-00 */
1198 	inp->in6p_flowinfo &= ~IPV6_FLOWLABEL_MASK;
1199 	if (inp->in6p_flags & IN6P_AUTOFLOWLABEL)
1200 		inp->in6p_flowinfo |=
1201 		    (htonl(ip6_randomflowlabel()) & IPV6_FLOWLABEL_MASK);
1202 	in_pcbrehash(inp);
1203 
1204 	/* Compute window scaling to request.  */
1205 	while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1206 	    (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat)
1207 		tp->request_r_scale++;
1208 
1209 	soisconnecting(so);
1210 	tcpstat.tcps_connattempt++;
1211 	tp->t_state = TCPS_SYN_SENT;
1212 	callout_reset(tp->tt_keep, tcp_keepinit, tcp_timer_keep, tp);
1213 	tp->iss = tcp_new_isn(tp);
1214 	tp->t_bw_rtseq = tp->iss;
1215 	tcp_sendseqinit(tp);
1216 
1217 	return 0;
1218 }
1219 #endif /* INET6 */
1220 
1221 /*
1222  * Export TCP internal state information via a struct tcp_info, based on the
1223  * Linux 2.6 API.  Not ABI compatible as our constants are mapped differently
1224  * (TCP state machine, etc).  We export all information using FreeBSD-native
1225  * constants -- for example, the numeric values for tcpi_state will differ
1226  * from Linux.
1227  */
1228 static void
1229 tcp_fill_info(struct tcpcb *tp, struct tcp_info *ti)
1230 {
1231 
1232 	INP_LOCK_ASSERT(tp->t_inpcb);
1233 	bzero(ti, sizeof(*ti));
1234 
1235 	ti->tcpi_state = tp->t_state;
1236 	if ((tp->t_flags & TF_REQ_TSTMP) && (tp->t_flags & TF_RCVD_TSTMP))
1237 		ti->tcpi_options |= TCPI_OPT_TIMESTAMPS;
1238 	if (tp->sack_enable)
1239 		ti->tcpi_options |= TCPI_OPT_SACK;
1240 	if ((tp->t_flags & TF_REQ_SCALE) && (tp->t_flags & TF_RCVD_SCALE)) {
1241 		ti->tcpi_options |= TCPI_OPT_WSCALE;
1242 		ti->tcpi_snd_wscale = tp->snd_scale;
1243 		ti->tcpi_rcv_wscale = tp->rcv_scale;
1244 	}
1245 
1246 	ti->tcpi_rtt = ((u_int64_t)tp->t_srtt * tick) >> TCP_RTT_SHIFT;
1247 	ti->tcpi_rttvar = ((u_int64_t)tp->t_rttvar * tick) >> TCP_RTTVAR_SHIFT;
1248 
1249 	ti->tcpi_snd_ssthresh = tp->snd_ssthresh;
1250 	ti->tcpi_snd_cwnd = tp->snd_cwnd;
1251 
1252 	/*
1253 	 * FreeBSD-specific extension fields for tcp_info.
1254 	 */
1255 	ti->tcpi_rcv_space = tp->rcv_wnd;
1256 	ti->tcpi_snd_wnd = tp->snd_wnd;
1257 	ti->tcpi_snd_bwnd = tp->snd_bwnd;
1258 }
1259 
1260 /*
1261  * The new sockopt interface makes it possible for us to block in the
1262  * copyin/out step (if we take a page fault).  Taking a page fault at
1263  * splnet() is probably a Bad Thing.  (Since sockets and pcbs both now
1264  * use TSM, there probably isn't any need for this function to run at
1265  * splnet() any more.  This needs more examination.)
1266  *
1267  * XXXRW: The locking here is wrong; we may take a page fault while holding
1268  * the inpcb lock.
1269  */
1270 int
1271 tcp_ctloutput(struct socket *so, struct sockopt *sopt)
1272 {
1273 	int	error, opt, optval;
1274 	struct	inpcb *inp;
1275 	struct	tcpcb *tp;
1276 	struct	tcp_info ti;
1277 
1278 	error = 0;
1279 	inp = sotoinpcb(so);
1280 	KASSERT(inp != NULL, ("tcp_ctloutput: inp == NULL"));
1281 	INP_LOCK(inp);
1282 	if (sopt->sopt_level != IPPROTO_TCP) {
1283 		INP_UNLOCK(inp);
1284 #ifdef INET6
1285 		if (INP_CHECK_SOCKAF(so, AF_INET6))
1286 			error = ip6_ctloutput(so, sopt);
1287 		else
1288 #endif /* INET6 */
1289 		error = ip_ctloutput(so, sopt);
1290 		return (error);
1291 	}
1292 	if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
1293 		error = ECONNRESET;
1294 		goto out;
1295 	}
1296 	tp = intotcpcb(inp);
1297 
1298 	switch (sopt->sopt_dir) {
1299 	case SOPT_SET:
1300 		switch (sopt->sopt_name) {
1301 #ifdef TCP_SIGNATURE
1302 		case TCP_MD5SIG:
1303 			error = sooptcopyin(sopt, &optval, sizeof optval,
1304 					    sizeof optval);
1305 			if (error)
1306 				break;
1307 
1308 			if (optval > 0)
1309 				tp->t_flags |= TF_SIGNATURE;
1310 			else
1311 				tp->t_flags &= ~TF_SIGNATURE;
1312 			break;
1313 #endif /* TCP_SIGNATURE */
1314 		case TCP_NODELAY:
1315 		case TCP_NOOPT:
1316 			error = sooptcopyin(sopt, &optval, sizeof optval,
1317 					    sizeof optval);
1318 			if (error)
1319 				break;
1320 
1321 			switch (sopt->sopt_name) {
1322 			case TCP_NODELAY:
1323 				opt = TF_NODELAY;
1324 				break;
1325 			case TCP_NOOPT:
1326 				opt = TF_NOOPT;
1327 				break;
1328 			default:
1329 				opt = 0; /* dead code to fool gcc */
1330 				break;
1331 			}
1332 
1333 			if (optval)
1334 				tp->t_flags |= opt;
1335 			else
1336 				tp->t_flags &= ~opt;
1337 			break;
1338 
1339 		case TCP_NOPUSH:
1340 			error = sooptcopyin(sopt, &optval, sizeof optval,
1341 					    sizeof optval);
1342 			if (error)
1343 				break;
1344 
1345 			if (optval)
1346 				tp->t_flags |= TF_NOPUSH;
1347 			else {
1348 				tp->t_flags &= ~TF_NOPUSH;
1349 				error = tcp_output(tp);
1350 			}
1351 			break;
1352 
1353 		case TCP_MAXSEG:
1354 			error = sooptcopyin(sopt, &optval, sizeof optval,
1355 					    sizeof optval);
1356 			if (error)
1357 				break;
1358 
1359 			if (optval > 0 && optval <= tp->t_maxseg &&
1360 			    optval + 40 >= tcp_minmss)
1361 				tp->t_maxseg = optval;
1362 			else
1363 				error = EINVAL;
1364 			break;
1365 
1366 		case TCP_INFO:
1367 			error = EINVAL;
1368 			break;
1369 
1370 		default:
1371 			error = ENOPROTOOPT;
1372 			break;
1373 		}
1374 		break;
1375 
1376 	case SOPT_GET:
1377 		switch (sopt->sopt_name) {
1378 #ifdef TCP_SIGNATURE
1379 		case TCP_MD5SIG:
1380 			optval = (tp->t_flags & TF_SIGNATURE) ? 1 : 0;
1381 			error = sooptcopyout(sopt, &optval, sizeof optval);
1382 			break;
1383 #endif
1384 		case TCP_NODELAY:
1385 			optval = tp->t_flags & TF_NODELAY;
1386 			error = sooptcopyout(sopt, &optval, sizeof optval);
1387 			break;
1388 		case TCP_MAXSEG:
1389 			optval = tp->t_maxseg;
1390 			error = sooptcopyout(sopt, &optval, sizeof optval);
1391 			break;
1392 		case TCP_NOOPT:
1393 			optval = tp->t_flags & TF_NOOPT;
1394 			error = sooptcopyout(sopt, &optval, sizeof optval);
1395 			break;
1396 		case TCP_NOPUSH:
1397 			optval = tp->t_flags & TF_NOPUSH;
1398 			error = sooptcopyout(sopt, &optval, sizeof optval);
1399 			break;
1400 		case TCP_INFO:
1401 			tcp_fill_info(tp, &ti);
1402 			error = sooptcopyout(sopt, &ti, sizeof ti);
1403 			break;
1404 		default:
1405 			error = ENOPROTOOPT;
1406 			break;
1407 		}
1408 		break;
1409 	}
1410 out:
1411 	INP_UNLOCK(inp);
1412 	return (error);
1413 }
1414 
1415 /*
1416  * tcp_sendspace and tcp_recvspace are the default send and receive window
1417  * sizes, respectively.  These are obsolescent (this information should
1418  * be set by the route).
1419  */
1420 u_long	tcp_sendspace = 1024*32;
1421 SYSCTL_ULONG(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace, CTLFLAG_RW,
1422     &tcp_sendspace , 0, "Maximum outgoing TCP datagram size");
1423 u_long	tcp_recvspace = 1024*64;
1424 SYSCTL_ULONG(_net_inet_tcp, TCPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
1425     &tcp_recvspace , 0, "Maximum incoming TCP datagram size");
1426 
1427 /*
1428  * Attach TCP protocol to socket, allocating
1429  * internet protocol control block, tcp control block,
1430  * bufer space, and entering LISTEN state if to accept connections.
1431  */
1432 static int
1433 tcp_attach(struct socket *so)
1434 {
1435 	struct tcpcb *tp;
1436 	struct inpcb *inp;
1437 	int error;
1438 #ifdef INET6
1439 	int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6) != 0;
1440 #endif
1441 
1442 	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
1443 		error = soreserve(so, tcp_sendspace, tcp_recvspace);
1444 		if (error)
1445 			return (error);
1446 	}
1447 	so->so_rcv.sb_flags |= SB_AUTOSIZE;
1448 	so->so_snd.sb_flags |= SB_AUTOSIZE;
1449 	INP_INFO_WLOCK(&tcbinfo);
1450 	error = in_pcballoc(so, &tcbinfo);
1451 	if (error) {
1452 		INP_INFO_WUNLOCK(&tcbinfo);
1453 		return (error);
1454 	}
1455 	inp = sotoinpcb(so);
1456 #ifdef INET6
1457 	if (isipv6) {
1458 		inp->inp_vflag |= INP_IPV6;
1459 		inp->in6p_hops = -1;	/* use kernel default */
1460 	}
1461 	else
1462 #endif
1463 	inp->inp_vflag |= INP_IPV4;
1464 	tp = tcp_newtcpcb(inp);
1465 	if (tp == NULL) {
1466 #ifdef INET6
1467 		if (isipv6) {
1468 			in6_pcbdetach(inp);
1469 			in6_pcbfree(inp);
1470 		} else {
1471 #endif
1472 			in_pcbdetach(inp);
1473 			in_pcbfree(inp);
1474 #ifdef INET6
1475 		}
1476 #endif
1477 		INP_INFO_WUNLOCK(&tcbinfo);
1478 		return (ENOBUFS);
1479 	}
1480 	tp->t_state = TCPS_CLOSED;
1481 	INP_UNLOCK(inp);
1482 	INP_INFO_WUNLOCK(&tcbinfo);
1483 	return (0);
1484 }
1485 
1486 /*
1487  * Initiate (or continue) disconnect.
1488  * If embryonic state, just send reset (once).
1489  * If in ``let data drain'' option and linger null, just drop.
1490  * Otherwise (hard), mark socket disconnecting and drop
1491  * current input data; switch states based on user close, and
1492  * send segment to peer (with FIN).
1493  */
1494 static void
1495 tcp_disconnect(struct tcpcb *tp)
1496 {
1497 	struct inpcb *inp = tp->t_inpcb;
1498 	struct socket *so = inp->inp_socket;
1499 
1500 	INP_INFO_WLOCK_ASSERT(&tcbinfo);
1501 	INP_LOCK_ASSERT(inp);
1502 
1503 	/*
1504 	 * Neither tcp_close() nor tcp_drop() should return NULL, as the
1505 	 * socket is still open.
1506 	 */
1507 	if (tp->t_state < TCPS_ESTABLISHED) {
1508 		tp = tcp_close(tp);
1509 		KASSERT(tp != NULL,
1510 		    ("tcp_disconnect: tcp_close() returned NULL"));
1511 	} else if ((so->so_options & SO_LINGER) && so->so_linger == 0) {
1512 		tp = tcp_drop(tp, 0);
1513 		KASSERT(tp != NULL,
1514 		    ("tcp_disconnect: tcp_drop() returned NULL"));
1515 	} else {
1516 		soisdisconnecting(so);
1517 		sbflush(&so->so_rcv);
1518 		tcp_usrclosed(tp);
1519 		if (!(inp->inp_vflag & INP_DROPPED))
1520 			tcp_output(tp);
1521 	}
1522 }
1523 
1524 /*
1525  * User issued close, and wish to trail through shutdown states:
1526  * if never received SYN, just forget it.  If got a SYN from peer,
1527  * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
1528  * If already got a FIN from peer, then almost done; go to LAST_ACK
1529  * state.  In all other cases, have already sent FIN to peer (e.g.
1530  * after PRU_SHUTDOWN), and just have to play tedious game waiting
1531  * for peer to send FIN or not respond to keep-alives, etc.
1532  * We can let the user exit from the close as soon as the FIN is acked.
1533  */
1534 static void
1535 tcp_usrclosed(struct tcpcb *tp)
1536 {
1537 
1538 	INP_INFO_WLOCK_ASSERT(&tcbinfo);
1539 	INP_LOCK_ASSERT(tp->t_inpcb);
1540 
1541 	switch (tp->t_state) {
1542 
1543 	case TCPS_CLOSED:
1544 	case TCPS_LISTEN:
1545 		tp->t_state = TCPS_CLOSED;
1546 		tp = tcp_close(tp);
1547 		/*
1548 		 * tcp_close() should never return NULL here as the socket is
1549 		 * still open.
1550 		 */
1551 		KASSERT(tp != NULL,
1552 		    ("tcp_usrclosed: tcp_close() returned NULL"));
1553 		break;
1554 
1555 	case TCPS_SYN_SENT:
1556 	case TCPS_SYN_RECEIVED:
1557 		tp->t_flags |= TF_NEEDFIN;
1558 		break;
1559 
1560 	case TCPS_ESTABLISHED:
1561 		tp->t_state = TCPS_FIN_WAIT_1;
1562 		break;
1563 
1564 	case TCPS_CLOSE_WAIT:
1565 		tp->t_state = TCPS_LAST_ACK;
1566 		break;
1567 	}
1568 	if (tp && tp->t_state >= TCPS_FIN_WAIT_2) {
1569 		soisdisconnected(tp->t_inpcb->inp_socket);
1570 		/* To prevent the connection hanging in FIN_WAIT_2 forever. */
1571 		if (tp->t_state == TCPS_FIN_WAIT_2) {
1572 			int timeout;
1573 
1574 			timeout = (tcp_fast_finwait2_recycle) ?
1575 				tcp_finwait2_timeout : tcp_maxidle;
1576 			callout_reset(tp->tt_2msl, timeout,
1577 				      tcp_timer_2msl, tp);
1578 		}
1579 	}
1580 }
1581 
1582 #ifdef DDB
1583 static void
1584 db_print_indent(int indent)
1585 {
1586 	int i;
1587 
1588 	for (i = 0; i < indent; i++)
1589 		db_printf(" ");
1590 }
1591 
1592 static void
1593 db_print_tstate(int t_state)
1594 {
1595 
1596 	switch (t_state) {
1597 	case TCPS_CLOSED:
1598 		db_printf("TCPS_CLOSED");
1599 		return;
1600 
1601 	case TCPS_LISTEN:
1602 		db_printf("TCPS_LISTEN");
1603 		return;
1604 
1605 	case TCPS_SYN_SENT:
1606 		db_printf("TCPS_SYN_SENT");
1607 		return;
1608 
1609 	case TCPS_SYN_RECEIVED:
1610 		db_printf("TCPS_SYN_RECEIVED");
1611 		return;
1612 
1613 	case TCPS_ESTABLISHED:
1614 		db_printf("TCPS_ESTABLISHED");
1615 		return;
1616 
1617 	case TCPS_CLOSE_WAIT:
1618 		db_printf("TCPS_CLOSE_WAIT");
1619 		return;
1620 
1621 	case TCPS_FIN_WAIT_1:
1622 		db_printf("TCPS_FIN_WAIT_1");
1623 		return;
1624 
1625 	case TCPS_CLOSING:
1626 		db_printf("TCPS_CLOSING");
1627 		return;
1628 
1629 	case TCPS_LAST_ACK:
1630 		db_printf("TCPS_LAST_ACK");
1631 		return;
1632 
1633 	case TCPS_FIN_WAIT_2:
1634 		db_printf("TCPS_FIN_WAIT_2");
1635 		return;
1636 
1637 	case TCPS_TIME_WAIT:
1638 		db_printf("TCPS_TIME_WAIT");
1639 		return;
1640 
1641 	default:
1642 		db_printf("unknown");
1643 		return;
1644 	}
1645 }
1646 
1647 static void
1648 db_print_tflags(u_int t_flags)
1649 {
1650 	int comma;
1651 
1652 	comma = 0;
1653 	if (t_flags & TF_ACKNOW) {
1654 		db_printf("%sTF_ACKNOW", comma ? ", " : "");
1655 		comma = 1;
1656 	}
1657 	if (t_flags & TF_DELACK) {
1658 		db_printf("%sTF_DELACK", comma ? ", " : "");
1659 		comma = 1;
1660 	}
1661 	if (t_flags & TF_NODELAY) {
1662 		db_printf("%sTF_NODELAY", comma ? ", " : "");
1663 		comma = 1;
1664 	}
1665 	if (t_flags & TF_NOOPT) {
1666 		db_printf("%sTF_NOOPT", comma ? ", " : "");
1667 		comma = 1;
1668 	}
1669 	if (t_flags & TF_SENTFIN) {
1670 		db_printf("%sTF_SENTFIN", comma ? ", " : "");
1671 		comma = 1;
1672 	}
1673 	if (t_flags & TF_REQ_SCALE) {
1674 		db_printf("%sTF_REQ_SCALE", comma ? ", " : "");
1675 		comma = 1;
1676 	}
1677 	if (t_flags & TF_RCVD_SCALE) {
1678 		db_printf("%sTF_RECVD_SCALE", comma ? ", " : "");
1679 		comma = 1;
1680 	}
1681 	if (t_flags & TF_REQ_TSTMP) {
1682 		db_printf("%sTF_REQ_TSTMP", comma ? ", " : "");
1683 		comma = 1;
1684 	}
1685 	if (t_flags & TF_RCVD_TSTMP) {
1686 		db_printf("%sTF_RCVD_TSTMP", comma ? ", " : "");
1687 		comma = 1;
1688 	}
1689 	if (t_flags & TF_SACK_PERMIT) {
1690 		db_printf("%sTF_SACK_PERMIT", comma ? ", " : "");
1691 		comma = 1;
1692 	}
1693 	if (t_flags & TF_NEEDSYN) {
1694 		db_printf("%sTF_NEEDSYN", comma ? ", " : "");
1695 		comma = 1;
1696 	}
1697 	if (t_flags & TF_NEEDFIN) {
1698 		db_printf("%sTF_NEEDFIN", comma ? ", " : "");
1699 		comma = 1;
1700 	}
1701 	if (t_flags & TF_NOPUSH) {
1702 		db_printf("%sTF_NOPUSH", comma ? ", " : "");
1703 		comma = 1;
1704 	}
1705 	if (t_flags & TF_NOPUSH) {
1706 		db_printf("%sTF_NOPUSH", comma ? ", " : "");
1707 		comma = 1;
1708 	}
1709 	if (t_flags & TF_MORETOCOME) {
1710 		db_printf("%sTF_MORETOCOME", comma ? ", " : "");
1711 		comma = 1;
1712 	}
1713 	if (t_flags & TF_LQ_OVERFLOW) {
1714 		db_printf("%sTF_LQ_OVERFLOW", comma ? ", " : "");
1715 		comma = 1;
1716 	}
1717 	if (t_flags & TF_LASTIDLE) {
1718 		db_printf("%sTF_LASTIDLE", comma ? ", " : "");
1719 		comma = 1;
1720 	}
1721 	if (t_flags & TF_RXWIN0SENT) {
1722 		db_printf("%sTF_RXWIN0SENT", comma ? ", " : "");
1723 		comma = 1;
1724 	}
1725 	if (t_flags & TF_FASTRECOVERY) {
1726 		db_printf("%sTF_FASTRECOVERY", comma ? ", " : "");
1727 		comma = 1;
1728 	}
1729 	if (t_flags & TF_WASFRECOVERY) {
1730 		db_printf("%sTF_WASFRECOVERY", comma ? ", " : "");
1731 		comma = 1;
1732 	}
1733 	if (t_flags & TF_SIGNATURE) {
1734 		db_printf("%sTF_SIGNATURE", comma ? ", " : "");
1735 		comma = 1;
1736 	}
1737 	if (t_flags & TF_FORCEDATA) {
1738 		db_printf("%sTF_FORCEDATA", comma ? ", " : "");
1739 		comma = 1;
1740 	}
1741 	if (t_flags & TF_TSO) {
1742 		db_printf("%sTF_TSO", comma ? ", " : "");
1743 		comma = 1;
1744 	}
1745 }
1746 
1747 static void
1748 db_print_toobflags(char t_oobflags)
1749 {
1750 	int comma;
1751 
1752 	comma = 0;
1753 	if (t_oobflags & TCPOOB_HAVEDATA) {
1754 		db_printf("%sTCPOOB_HAVEDATA", comma ? ", " : "");
1755 		comma = 1;
1756 	}
1757 	if (t_oobflags & TCPOOB_HADDATA) {
1758 		db_printf("%sTCPOOB_HADDATA", comma ? ", " : "");
1759 		comma = 1;
1760 	}
1761 }
1762 
1763 static void
1764 db_print_tcpcb(struct tcpcb *tp, const char *name, int indent)
1765 {
1766 
1767 	db_print_indent(indent);
1768 	db_printf("%s at %p\n", name, tp);
1769 
1770 	indent += 2;
1771 
1772 	db_print_indent(indent);
1773 	db_printf("t_segq first: %p   t_segqlen: %d   t_dupacks: %d\n",
1774 	   LIST_FIRST(&tp->t_segq), tp->t_segqlen, tp->t_dupacks);
1775 
1776 	db_print_indent(indent);
1777 	db_printf("tt_rexmt: %p   tt_persist: %p   tt_keep: %p\n",
1778 	    tp->tt_rexmt, tp->tt_persist, tp->tt_keep);
1779 
1780 	db_print_indent(indent);
1781 	db_printf("tt_2msl: %p   tt_delack: %p   t_inpcb: %p\n", tp->tt_2msl,
1782 	    tp->tt_delack, tp->t_inpcb);
1783 
1784 	db_print_indent(indent);
1785 	db_printf("t_state: %d (", tp->t_state);
1786 	db_print_tstate(tp->t_state);
1787 	db_printf(")\n");
1788 
1789 	db_print_indent(indent);
1790 	db_printf("t_flags: 0x%x (", tp->t_flags);
1791 	db_print_tflags(tp->t_flags);
1792 	db_printf(")\n");
1793 
1794 	db_print_indent(indent);
1795 	db_printf("snd_una: 0x%08x   snd_max: 0x%08x   snd_nxt: x0%08x\n",
1796 	    tp->snd_una, tp->snd_max, tp->snd_nxt);
1797 
1798 	db_print_indent(indent);
1799 	db_printf("snd_up: 0x%08x   snd_wl1: 0x%08x   snd_wl2: 0x%08x\n",
1800 	   tp->snd_up, tp->snd_wl1, tp->snd_wl2);
1801 
1802 	db_print_indent(indent);
1803 	db_printf("iss: 0x%08x   irs: 0x%08x   rcv_nxt: 0x%08x\n",
1804 	    tp->iss, tp->irs, tp->rcv_nxt);
1805 
1806 	db_print_indent(indent);
1807 	db_printf("rcv_adv: 0x%08x   rcv_wnd: %lu   rcv_up: 0x%08x\n",
1808 	    tp->rcv_adv, tp->rcv_wnd, tp->rcv_up);
1809 
1810 	db_print_indent(indent);
1811 	db_printf("snd_wnd: %lu   snd_cwnd: %lu   snd_bwnd: %lu\n",
1812 	   tp->snd_wnd, tp->snd_cwnd, tp->snd_bwnd);
1813 
1814 	db_print_indent(indent);
1815 	db_printf("snd_ssthresh: %lu   snd_bandwidth: %lu   snd_recover: "
1816 	    "0x%08x\n", tp->snd_ssthresh, tp->snd_bandwidth,
1817 	    tp->snd_recover);
1818 
1819 	db_print_indent(indent);
1820 	db_printf("t_maxopd: %u   t_rcvtime: %lu   t_startime: %lu\n",
1821 	    tp->t_maxopd, tp->t_rcvtime, tp->t_starttime);
1822 
1823 	db_print_indent(indent);
1824 	db_printf("t_rttime: %d   t_rtsq: 0x%08x   t_bw_rtttime: %d\n",
1825 	    tp->t_rtttime, tp->t_rtseq, tp->t_bw_rtttime);
1826 
1827 	db_print_indent(indent);
1828 	db_printf("t_bw_rtseq: 0x%08x   t_rxtcur: %d   t_maxseg: %u   "
1829 	    "t_srtt: %d\n", tp->t_bw_rtseq, tp->t_rxtcur, tp->t_maxseg,
1830 	    tp->t_srtt);
1831 
1832 	db_print_indent(indent);
1833 	db_printf("t_rttvar: %d   t_rxtshift: %d   t_rttmin: %u   "
1834 	    "t_rttbest: %u\n", tp->t_rttvar, tp->t_rxtshift, tp->t_rttmin,
1835 	    tp->t_rttbest);
1836 
1837 	db_print_indent(indent);
1838 	db_printf("t_rttupdated: %lu   max_sndwnd: %lu   t_softerror: %d\n",
1839 	    tp->t_rttupdated, tp->max_sndwnd, tp->t_softerror);
1840 
1841 	db_print_indent(indent);
1842 	db_printf("t_oobflags: 0x%x (", tp->t_oobflags);
1843 	db_print_toobflags(tp->t_oobflags);
1844 	db_printf(")   t_iobc: 0x%02x\n", tp->t_iobc);
1845 
1846 	db_print_indent(indent);
1847 	db_printf("snd_scale: %u   rcv_scale: %u   request_r_scale: %u\n",
1848 	    tp->snd_scale, tp->rcv_scale, tp->request_r_scale);
1849 
1850 	db_print_indent(indent);
1851 	db_printf("requested_s_scale: %u   ts_recent: %u   ts_recent_age: "
1852 	    "%lu\n", tp->requested_s_scale, tp->ts_recent, tp->ts_recent_age);
1853 
1854 	db_print_indent(indent);
1855 	db_printf("ts_offset: %u   last_ack_sent: 0x%08x   snd_cwnd_prev: "
1856 	    "%lu\n", tp->ts_offset, tp->last_ack_sent, tp->snd_cwnd_prev);
1857 
1858 	db_print_indent(indent);
1859 	db_printf("snd_ssthresh_prev: %lu   snd_recover_prev: 0x%08x   "
1860 	    "t_badrxtwin: %lu\n", tp->snd_ssthresh_prev,
1861 	    tp->snd_recover_prev, tp->t_badrxtwin);
1862 
1863 	db_print_indent(indent);
1864 	db_printf("sack_enable: %d   snd_numholes: %d  snd_holes first: %p\n",
1865 	    tp->sack_enable, tp->snd_numholes, TAILQ_FIRST(&tp->snd_holes));
1866 
1867 	db_print_indent(indent);
1868 	db_printf("snd_fack: 0x%08x   rcv_numsacks: %d   sack_newdata: "
1869 	    "0x%08x\n", tp->snd_fack, tp->rcv_numsacks, tp->sack_newdata);
1870 
1871 	/* Skip sackblks, sackhint. */
1872 
1873 	db_print_indent(indent);
1874 	db_printf("t_rttlow: %d   rfbuf_ts: %u   rfbuf_cnt: %d\n",
1875 	    tp->t_rttlow, tp->rfbuf_ts, tp->rfbuf_cnt);
1876 }
1877 
1878 DB_SHOW_COMMAND(tcpcb, db_show_tcpcb)
1879 {
1880 	struct tcpcb *tp;
1881 
1882 	if (!have_addr) {
1883 		db_printf("usage: show tcpcb <addr>\n");
1884 		return;
1885 	}
1886 	tp = (struct tcpcb *)addr;
1887 
1888 	db_print_tcpcb(tp, "tcpcb", 0);
1889 }
1890 #endif
1891