1/*
2 * Copyright (c) 1982, 1986, 1988, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 * From: @(#)tcp_usrreq.c 8.2 (Berkeley) 1/3/94
34 * $FreeBSD: head/sys/netinet/tcp_usrreq.c 127505 2004-03-27 21:05:46Z pjd $
35 */
36
37#include "opt_ipsec.h"
38#include "opt_inet.h"
39#include "opt_inet6.h"
40#include "opt_tcpdebug.h"
41
42#include <sys/param.h>
43#include <sys/systm.h>
44#include <sys/malloc.h>
45#include <sys/kernel.h>
46#include <sys/sysctl.h>
47#include <sys/mbuf.h>
48#ifdef INET6
49#include <sys/domain.h>
50#endif /* INET6 */
51#include <sys/socket.h>
52#include <sys/socketvar.h>
53#include <sys/protosw.h>
54#include <sys/proc.h>
55#include <sys/jail.h>
56
57#include <net/if.h>
58#include <net/route.h>
59
60#include <netinet/in.h>
61#include <netinet/in_systm.h>
62#ifdef INET6
63#include <netinet/ip6.h>
64#endif
65#include <netinet/in_pcb.h>
66#ifdef INET6
67#include <netinet6/in6_pcb.h>
68#endif
69#include <netinet/in_var.h>
70#include <netinet/ip_var.h>
71#ifdef INET6
72#include <netinet6/ip6_var.h>
73#endif
74#include <netinet/tcp.h>
75#include <netinet/tcp_fsm.h>
76#include <netinet/tcp_seq.h>
77#include <netinet/tcp_timer.h>
78#include <netinet/tcp_var.h>
79#include <netinet/tcpip.h>
80#ifdef TCPDEBUG
81#include <netinet/tcp_debug.h>
82#endif
83
84#ifdef IPSEC
85#include <netinet6/ipsec.h>
86#endif /*IPSEC*/
87
88/*
89 * TCP protocol interface to socket abstraction.
90 */
91extern char *tcpstates[]; /* XXX ??? */
92
93static int tcp_attach(struct socket *, struct thread *td);
94static int tcp_connect(struct tcpcb *, struct sockaddr *,
95 struct thread *td);
96#ifdef INET6
97static int tcp6_connect(struct tcpcb *, struct sockaddr *,
98 struct thread *td);
99#endif /* INET6 */
100static struct tcpcb *
101 tcp_disconnect(struct tcpcb *);
102static struct tcpcb *
103 tcp_usrclosed(struct tcpcb *);
104
105#ifdef TCPDEBUG
106#define TCPDEBUG0 int ostate = 0
107#define TCPDEBUG1() ostate = tp ? tp->t_state : 0
108#define TCPDEBUG2(req) if (tp && (so->so_options & SO_DEBUG)) \
109 tcp_trace(TA_USER, ostate, tp, 0, 0, req)
110#else
111#define TCPDEBUG0
112#define TCPDEBUG1()
113#define TCPDEBUG2(req)
114#endif
115
116/*
117 * TCP attaches to socket via pru_attach(), reserving space,
118 * and an internet control block.
119 */
120static int
121tcp_usr_attach(struct socket *so, int proto, struct thread *td)
122{
123 int s = splnet();
124 int error;
125 struct inpcb *inp;
126 struct tcpcb *tp = 0;
127 TCPDEBUG0;
128
129 INP_INFO_WLOCK(&tcbinfo);
130 TCPDEBUG1();
131 inp = sotoinpcb(so);
132 if (inp) {
133 error = EISCONN;
134 goto out;
135 }
136
137 error = tcp_attach(so, td);
138 if (error)
139 goto out;
140
141 if ((so->so_options & SO_LINGER) && so->so_linger == 0)
142 so->so_linger = TCP_LINGERTIME;
143
144 inp = sotoinpcb(so);
145 tp = intotcpcb(inp);
146out:
147 TCPDEBUG2(PRU_ATTACH);
148 INP_INFO_WUNLOCK(&tcbinfo);
149 splx(s);
150 return error;
151}
152
153/*
154 * pru_detach() detaches the TCP protocol from the socket.
155 * If the protocol state is non-embryonic, then can't
156 * do this directly: have to initiate a pru_disconnect(),
157 * which may finish later; embryonic TCB's can just
158 * be discarded here.
159 */
160static int
161tcp_usr_detach(struct socket *so)
162{
163 int s = splnet();
164 int error = 0;
165 struct inpcb *inp;
166 struct tcpcb *tp;
167 TCPDEBUG0;
168
169 INP_INFO_WLOCK(&tcbinfo);
170 inp = sotoinpcb(so);
171 if (inp == 0) {
172 INP_INFO_WUNLOCK(&tcbinfo);
173 splx(s);
174 return EINVAL; /* XXX */
175 }
176 INP_LOCK(inp);
177 tp = intotcpcb(inp);
178 TCPDEBUG1();
179 tp = tcp_disconnect(tp);
180
181 TCPDEBUG2(PRU_DETACH);
182 if (tp)
183 INP_UNLOCK(inp);
184 INP_INFO_WUNLOCK(&tcbinfo);
185 splx(s);
186 return error;
187}
188
189#define INI_NOLOCK 0
190#define INI_READ 1
191#define INI_WRITE 2
192
193#define COMMON_START() \
194 TCPDEBUG0; \
195 do { \
196 if (inirw == INI_READ) \
197 INP_INFO_RLOCK(&tcbinfo); \
198 else if (inirw == INI_WRITE) \
199 INP_INFO_WLOCK(&tcbinfo); \
200 inp = sotoinpcb(so); \
201 if (inp == 0) { \
202 if (inirw == INI_READ) \
203 INP_INFO_RUNLOCK(&tcbinfo); \
204 else if (inirw == INI_WRITE) \
205 INP_INFO_WUNLOCK(&tcbinfo); \
206 splx(s); \
207 return EINVAL; \
208 } \
209 INP_LOCK(inp); \
210 if (inirw == INI_READ) \
211 INP_INFO_RUNLOCK(&tcbinfo); \
212 tp = intotcpcb(inp); \
213 TCPDEBUG1(); \
214} while(0)
215
216#define COMMON_END(req) \
217out: TCPDEBUG2(req); \
218 do { \
219 if (tp) \
220 INP_UNLOCK(inp); \
221 if (inirw == INI_WRITE) \
222 INP_INFO_WUNLOCK(&tcbinfo); \
223 splx(s); \
224 return error; \
225 goto out; \
226} while(0)
227
228/*
229 * Give the socket an address.
230 */
231static int
232tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
233{
234 int s = splnet();
235 int error = 0;
236 struct inpcb *inp;
237 struct tcpcb *tp;
238 struct sockaddr_in *sinp;
239 const int inirw = INI_WRITE;
240
241 COMMON_START();
242
243 /*
244 * Must check for multicast addresses and disallow binding
245 * to them.
246 */
247 sinp = (struct sockaddr_in *)nam;
248 if (nam->sa_len != sizeof (*sinp))
249 return (EINVAL);
250 if (sinp->sin_family == AF_INET &&
251 IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) {
252 error = EAFNOSUPPORT;
253 goto out;
254 }
255 error = in_pcbbind(inp, nam, td->td_ucred);
256 if (error)
257 goto out;
258 COMMON_END(PRU_BIND);
259}
260
261#ifdef INET6
262static int
263tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
264{
265 int s = splnet();
266 int error = 0;
267 struct inpcb *inp;
268 struct tcpcb *tp;
269 struct sockaddr_in6 *sin6p;
270 const int inirw = INI_WRITE;
271
272 COMMON_START();
273
274 /*
275 * Must check for multicast addresses and disallow binding
276 * to them.
277 */
278 sin6p = (struct sockaddr_in6 *)nam;
279 if (nam->sa_len != sizeof (*sin6p))
280 return (EINVAL);
281 if (sin6p->sin6_family == AF_INET6 &&
282 IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) {
283 error = EAFNOSUPPORT;
284 goto out;
285 }
286 inp->inp_vflag &= ~INP_IPV4;
287 inp->inp_vflag |= INP_IPV6;
288 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
289 if (IN6_IS_ADDR_UNSPECIFIED(&sin6p->sin6_addr))
290 inp->inp_vflag |= INP_IPV4;
291 else if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
292 struct sockaddr_in sin;
293
294 in6_sin6_2_sin(&sin, sin6p);
295 inp->inp_vflag |= INP_IPV4;
296 inp->inp_vflag &= ~INP_IPV6;
297 error = in_pcbbind(inp, (struct sockaddr *)&sin,
298 td->td_ucred);
299 goto out;
300 }
301 }
302 error = in6_pcbbind(inp, nam, td->td_ucred);
303 if (error)
304 goto out;
305 COMMON_END(PRU_BIND);
306}
307#endif /* INET6 */
308
309/*
310 * Prepare to accept connections.
311 */
312static int
313tcp_usr_listen(struct socket *so, struct thread *td)
314{
315 int s = splnet();
316 int error = 0;
317 struct inpcb *inp;
318 struct tcpcb *tp;
319 const int inirw = INI_WRITE;
320
321 COMMON_START();
322 if (inp->inp_lport == 0)
323 error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
324 if (error == 0)
325 tp->t_state = TCPS_LISTEN;
326 COMMON_END(PRU_LISTEN);
327}
328
329#ifdef INET6
330static int
331tcp6_usr_listen(struct socket *so, struct thread *td)
332{
333 int s = splnet();
334 int error = 0;
335 struct inpcb *inp;
336 struct tcpcb *tp;
337 const int inirw = INI_WRITE;
338
339 COMMON_START();
340 if (inp->inp_lport == 0) {
341 inp->inp_vflag &= ~INP_IPV4;
342 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
343 inp->inp_vflag |= INP_IPV4;
344 error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
345 }
346 if (error == 0)
347 tp->t_state = TCPS_LISTEN;
348 COMMON_END(PRU_LISTEN);
349}
350#endif /* INET6 */
351
352/*
353 * Initiate connection to peer.
354 * Create a template for use in transmissions on this connection.
355 * Enter SYN_SENT state, and mark socket as connecting.
356 * Start keep-alive timer, and seed output sequence space.
357 * Send initial segment on connection.
358 */
359static int
360tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
361{
362 int s = splnet();
363 int error = 0;
364 struct inpcb *inp;
365 struct tcpcb *tp;
366 struct sockaddr_in *sinp;
367 const int inirw = INI_WRITE;
368
369 COMMON_START();
370
371 /*
372 * Must disallow TCP ``connections'' to multicast addresses.
373 */
374 sinp = (struct sockaddr_in *)nam;
375 if (nam->sa_len != sizeof (*sinp))
376 return (EINVAL);
377 if (sinp->sin_family == AF_INET
378 && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) {
379 error = EAFNOSUPPORT;
380 goto out;
381 }
382
383 if (td && jailed(td->td_ucred))
384 prison_remote_ip(td->td_ucred, 0, &sinp->sin_addr.s_addr);
385
386 if ((error = tcp_connect(tp, nam, td)) != 0)
387 goto out;
388 error = tcp_output(tp);
389 COMMON_END(PRU_CONNECT);
390}
391
392#ifdef INET6
393static int
394tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
395{
396 int s = splnet();
397 int error = 0;
398 struct inpcb *inp;
399 struct tcpcb *tp;
400 struct sockaddr_in6 *sin6p;
401 const int inirw = INI_WRITE;
402
403 COMMON_START();
404
405 /*
406 * Must disallow TCP ``connections'' to multicast addresses.
407 */
408 sin6p = (struct sockaddr_in6 *)nam;
409 if (nam->sa_len != sizeof (*sin6p))
410 return (EINVAL);
411 if (sin6p->sin6_family == AF_INET6
412 && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) {
413 error = EAFNOSUPPORT;
414 goto out;
415 }
416
417 if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
418 struct sockaddr_in sin;
419
420 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
421 error = EINVAL;
422 goto out;
423 }
424
425 in6_sin6_2_sin(&sin, sin6p);
426 inp->inp_vflag |= INP_IPV4;
427 inp->inp_vflag &= ~INP_IPV6;
428 if ((error = tcp_connect(tp, (struct sockaddr *)&sin, td)) != 0)
429 goto out;
430 error = tcp_output(tp);
431 goto out;
432 }
433 inp->inp_vflag &= ~INP_IPV4;
434 inp->inp_vflag |= INP_IPV6;
435 inp->inp_inc.inc_isipv6 = 1;
436 if ((error = tcp6_connect(tp, nam, td)) != 0)
437 goto out;
438 error = tcp_output(tp);
439 COMMON_END(PRU_CONNECT);
440}
441#endif /* INET6 */
442
443/*
444 * Initiate disconnect from peer.
445 * If connection never passed embryonic stage, just drop;
446 * else if don't need to let data drain, then can just drop anyways,
447 * else have to begin TCP shutdown process: mark socket disconnecting,
448 * drain unread data, state switch to reflect user close, and
449 * send segment (e.g. FIN) to peer. Socket will be really disconnected
450 * when peer sends FIN and acks ours.
451 *
452 * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.
453 */
454static int
455tcp_usr_disconnect(struct socket *so)
456{
457 int s = splnet();
458 int error = 0;
459 struct inpcb *inp;
460 struct tcpcb *tp;
461 const int inirw = INI_WRITE;
462
463 COMMON_START();
464 tp = tcp_disconnect(tp);
465 COMMON_END(PRU_DISCONNECT);
466}
467
468/*
469 * Accept a connection. Essentially all the work is
470 * done at higher levels; just return the address
471 * of the peer, storing through addr.
472 */
473static int
474tcp_usr_accept(struct socket *so, struct sockaddr **nam)
475{
476 int s;
477 int error = 0;
478 struct inpcb *inp = NULL;
479 struct tcpcb *tp = NULL;
480 struct in_addr addr;
481 in_port_t port = 0;
482 TCPDEBUG0;
483
484 if (so->so_state & SS_ISDISCONNECTED) {
485 error = ECONNABORTED;
486 goto out;
487 }
488
489 s = splnet();
490 INP_INFO_RLOCK(&tcbinfo);
491 inp = sotoinpcb(so);
492 if (!inp) {
493 INP_INFO_RUNLOCK(&tcbinfo);
494 splx(s);
495 return (EINVAL);
496 }
497 INP_LOCK(inp);
498 INP_INFO_RUNLOCK(&tcbinfo);
499 tp = intotcpcb(inp);
500 TCPDEBUG1();
501
502 /*
503 * We inline in_setpeeraddr and COMMON_END here, so that we can
504 * copy the data of interest and defer the malloc until after we
505 * release the lock.
506 */
507 port = inp->inp_fport;
508 addr = inp->inp_faddr;
509
510out: TCPDEBUG2(PRU_ACCEPT);
511 if (tp)
512 INP_UNLOCK(inp);
513 splx(s);
514 if (error == 0)
515 *nam = in_sockaddr(port, &addr);
516 return error;
517}
518
519#ifdef INET6
520static int
521tcp6_usr_accept(struct socket *so, struct sockaddr **nam)
522{
523 int s;
524 struct inpcb *inp = NULL;
525 int error = 0;
526 struct tcpcb *tp = NULL;
527 struct in_addr addr;
528 struct in6_addr addr6;
529 in_port_t port = 0;
530 int v4 = 0;
531 TCPDEBUG0;
532
533 if (so->so_state & SS_ISDISCONNECTED) {
534 error = ECONNABORTED;
535 goto out;
536 }
537
538 s = splnet();
539 INP_INFO_RLOCK(&tcbinfo);
540 inp = sotoinpcb(so);
541 if (inp == 0) {
542 INP_INFO_RUNLOCK(&tcbinfo);
543 splx(s);
544 return (EINVAL);
545 }
546 INP_LOCK(inp);
547 INP_INFO_RUNLOCK(&tcbinfo);
548 tp = intotcpcb(inp);
549 TCPDEBUG1();
550 /*
551 * We inline in6_mapped_peeraddr and COMMON_END here, so that we can
552 * copy the data of interest and defer the malloc until after we
553 * release the lock.
554 */
555 if (inp->inp_vflag & INP_IPV4) {
556 v4 = 1;
557 port = inp->inp_fport;
558 addr = inp->inp_faddr;
559 } else {
560 port = inp->inp_fport;
561 addr6 = inp->in6p_faddr;
562 }
563
564out: TCPDEBUG2(PRU_ACCEPT);
565 if (tp)
566 INP_UNLOCK(inp);
567 splx(s);
568 if (error == 0) {
569 if (v4)
570 *nam = in6_v4mapsin6_sockaddr(port, &addr);
571 else
572 *nam = in6_sockaddr(port, &addr6);
573 }
574 return error;
575}
576#endif /* INET6 */
577
578/*
579 * This is the wrapper function for in_setsockaddr. We just pass down
580 * the pcbinfo for in_setsockaddr to lock. We don't want to do the locking
581 * here because in_setsockaddr will call malloc and can block.
582 */
583static int
584tcp_sockaddr(struct socket *so, struct sockaddr **nam)
585{
586 return (in_setsockaddr(so, nam, &tcbinfo));
587}
588
589/*
590 * This is the wrapper function for in_setpeeraddr. We just pass down
591 * the pcbinfo for in_setpeeraddr to lock.
592 */
593static int
594tcp_peeraddr(struct socket *so, struct sockaddr **nam)
595{
596 return (in_setpeeraddr(so, nam, &tcbinfo));
597}
598
599/*
600 * Mark the connection as being incapable of further output.
601 */
602static int
603tcp_usr_shutdown(struct socket *so)
604{
605 int s = splnet();
606 int error = 0;
607 struct inpcb *inp;
608 struct tcpcb *tp;
609 const int inirw = INI_WRITE;
610
611 COMMON_START();
612 socantsendmore(so);
613 tp = tcp_usrclosed(tp);
614 if (tp)
615 error = tcp_output(tp);
616 COMMON_END(PRU_SHUTDOWN);
617}
618
619/*
620 * After a receive, possibly send window update to peer.
621 */
622static int
623tcp_usr_rcvd(struct socket *so, int flags)
624{
625 int s = splnet();
626 int error = 0;
627 struct inpcb *inp;
628 struct tcpcb *tp;
629 const int inirw = INI_READ;
630
631 COMMON_START();
632 tcp_output(tp);
633 COMMON_END(PRU_RCVD);
634}
635
636/*
637 * Do a send by putting data in output queue and updating urgent
638 * marker if URG set. Possibly send more data. Unlike the other
639 * pru_*() routines, the mbuf chains are our responsibility. We
640 * must either enqueue them or free them. The other pru_* routines
641 * generally are caller-frees.
642 */
643static int
644tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
645 struct sockaddr *nam, struct mbuf *control, struct thread *td)
646{
647 int s = splnet();
648 int error = 0;
649 struct inpcb *inp;
650 struct tcpcb *tp;
651 const int inirw = INI_WRITE;
652#ifdef INET6
653 int isipv6;
654#endif
655 TCPDEBUG0;
656
657 /*
658 * Need write lock here because this function might call
659 * tcp_connect or tcp_usrclosed.
660 * We really want to have to this function upgrade from read lock
661 * to write lock. XXX
662 */
663 INP_INFO_WLOCK(&tcbinfo);
664 inp = sotoinpcb(so);
665 if (inp == NULL) {
666 /*
667 * OOPS! we lost a race, the TCP session got reset after
668 * we checked SS_CANTSENDMORE, eg: while doing uiomove or a
669 * network interrupt in the non-splnet() section of sosend().
670 */
671 if (m)
672 m_freem(m);
673 if (control)
674 m_freem(control);
675 error = ECONNRESET; /* XXX EPIPE? */
676 tp = NULL;
677 TCPDEBUG1();
678 goto out;
679 }
680 INP_LOCK(inp);
681#ifdef INET6
682 isipv6 = nam && nam->sa_family == AF_INET6;
683#endif /* INET6 */
684 tp = intotcpcb(inp);
685 TCPDEBUG1();
686 if (control) {
687 /* TCP doesn't do control messages (rights, creds, etc) */
688 if (control->m_len) {
689 m_freem(control);
690 if (m)
691 m_freem(m);
692 error = EINVAL;
693 goto out;
694 }
695 m_freem(control); /* empty control, just free it */
696 }
697 if (!(flags & PRUS_OOB)) {
698 sbappendstream(&so->so_snd, m);
699 if (nam && tp->t_state < TCPS_SYN_SENT) {
700 /*
701 * Do implied connect if not yet connected,
702 * initialize window to default value, and
703 * initialize maxseg/maxopd using peer's cached
704 * MSS.
705 */
706#ifdef INET6
707 if (isipv6)
708 error = tcp6_connect(tp, nam, td);
709 else
710#endif /* INET6 */
711 error = tcp_connect(tp, nam, td);
712 if (error)
713 goto out;
714 tp->snd_wnd = TTCP_CLIENT_SND_WND;
715 tcp_mss(tp, -1);
716 }
717
718 if (flags & PRUS_EOF) {
719 /*
720 * Close the send side of the connection after
721 * the data is sent.
722 */
723 socantsendmore(so);
724 tp = tcp_usrclosed(tp);
725 }
726 if (tp != NULL) {
727 if (flags & PRUS_MORETOCOME)
728 tp->t_flags |= TF_MORETOCOME;
729 error = tcp_output(tp);
730 if (flags & PRUS_MORETOCOME)
731 tp->t_flags &= ~TF_MORETOCOME;
732 }
733 } else {
734 if (sbspace(&so->so_snd) < -512) {
735 m_freem(m);
736 error = ENOBUFS;
737 goto out;
738 }
739 /*
740 * According to RFC961 (Assigned Protocols),
741 * the urgent pointer points to the last octet
742 * of urgent data. We continue, however,
743 * to consider it to indicate the first octet
744 * of data past the urgent section.
745 * Otherwise, snd_up should be one lower.
746 */
747 sbappendstream(&so->so_snd, m);
748 if (nam && tp->t_state < TCPS_SYN_SENT) {
749 /*
750 * Do implied connect if not yet connected,
751 * initialize window to default value, and
752 * initialize maxseg/maxopd using peer's cached
753 * MSS.
754 */
755#ifdef INET6
756 if (isipv6)
757 error = tcp6_connect(tp, nam, td);
758 else
759#endif /* INET6 */
760 error = tcp_connect(tp, nam, td);
761 if (error)
762 goto out;
763 tp->snd_wnd = TTCP_CLIENT_SND_WND;
764 tcp_mss(tp, -1);
765 }
766 tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
767 tp->t_force = 1;
768 error = tcp_output(tp);
769 tp->t_force = 0;
770 }
771 COMMON_END((flags & PRUS_OOB) ? PRU_SENDOOB :
772 ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
773}
774
775/*
776 * Abort the TCP.
777 */
778static int
779tcp_usr_abort(struct socket *so)
780{
781 int s = splnet();
782 int error = 0;
783 struct inpcb *inp;
784 struct tcpcb *tp;
785 const int inirw = INI_WRITE;
786
787 COMMON_START();
788 tp = tcp_drop(tp, ECONNABORTED);
789 COMMON_END(PRU_ABORT);
790}
791
792/*
793 * Receive out-of-band data.
794 */
795static int
796tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags)
797{
798 int s = splnet();
799 int error = 0;
800 struct inpcb *inp;
801 struct tcpcb *tp;
802 const int inirw = INI_READ;
803
804 COMMON_START();
805 if ((so->so_oobmark == 0 &&
806 (so->so_state & SS_RCVATMARK) == 0) ||
807 so->so_options & SO_OOBINLINE ||
808 tp->t_oobflags & TCPOOB_HADDATA) {
809 error = EINVAL;
810 goto out;
811 }
812 if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
813 error = EWOULDBLOCK;
814 goto out;
815 }
816 m->m_len = 1;
817 *mtod(m, caddr_t) = tp->t_iobc;
818 if ((flags & MSG_PEEK) == 0)
819 tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
820 COMMON_END(PRU_RCVOOB);
821}
822
823/* xxx - should be const */
824struct pr_usrreqs tcp_usrreqs = {
825 tcp_usr_abort, tcp_usr_accept, tcp_usr_attach, tcp_usr_bind,
826 tcp_usr_connect, pru_connect2_notsupp, in_control, tcp_usr_detach,
827 tcp_usr_disconnect, tcp_usr_listen, tcp_peeraddr, tcp_usr_rcvd,
828 tcp_usr_rcvoob, tcp_usr_send, pru_sense_null, tcp_usr_shutdown,
829 tcp_sockaddr, sosend, soreceive, sopoll, in_pcbsosetlabel
830};
831
832#ifdef INET6
833struct pr_usrreqs tcp6_usrreqs = {
834 tcp_usr_abort, tcp6_usr_accept, tcp_usr_attach, tcp6_usr_bind,
835 tcp6_usr_connect, pru_connect2_notsupp, in6_control, tcp_usr_detach,
836 tcp_usr_disconnect, tcp6_usr_listen, in6_mapped_peeraddr, tcp_usr_rcvd,
837 tcp_usr_rcvoob, tcp_usr_send, pru_sense_null, tcp_usr_shutdown,
838 in6_mapped_sockaddr, sosend, soreceive, sopoll, in_pcbsosetlabel
839};
840#endif /* INET6 */
841
842/*
843 * Common subroutine to open a TCP connection to remote host specified
844 * by struct sockaddr_in in mbuf *nam. Call in_pcbbind to assign a local
845 * port number if needed. Call in_pcbconnect_setup to do the routing and
846 * to choose a local host address (interface). If there is an existing
847 * incarnation of the same connection in TIME-WAIT state and if the remote
848 * host was sending CC options and if the connection duration was < MSL, then
849 * truncate the previous TIME-WAIT state and proceed.
850 * Initialize connection parameters and enter SYN-SENT state.
851 */
852static int
853tcp_connect(tp, nam, td)
854 register struct tcpcb *tp;
855 struct sockaddr *nam;
856 struct thread *td;
857{
858 struct inpcb *inp = tp->t_inpcb, *oinp;
859 struct socket *so = inp->inp_socket;
860 struct tcptw *otw;
861 struct rmxp_tao tao;
862 struct in_addr laddr;
863 u_short lport;
864 int error;
865
866 bzero(&tao, sizeof(tao));
867
868 if (inp->inp_lport == 0) {
869 error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
870 if (error)
871 return error;
872 }
873
874 /*
875 * Cannot simply call in_pcbconnect, because there might be an
876 * earlier incarnation of this same connection still in
877 * TIME_WAIT state, creating an ADDRINUSE error.
878 */
879 laddr = inp->inp_laddr;
880 lport = inp->inp_lport;
881 error = in_pcbconnect_setup(inp, nam, &laddr.s_addr, &lport,
882 &inp->inp_faddr.s_addr, &inp->inp_fport, &oinp, td->td_ucred);
883 if (error && oinp == NULL)
884 return error;
885 if (oinp) {
886 if (oinp != inp &&
887 (oinp->inp_vflag & INP_TIMEWAIT) &&
888 (ticks - (otw = intotw(oinp))->t_starttime) < tcp_msl &&
889 otw->cc_recv != 0) {
890 inp->inp_faddr = oinp->inp_faddr;
891 inp->inp_fport = oinp->inp_fport;
892 (void) tcp_twclose(otw, 0);
893 } else
894 return EADDRINUSE;
895 }
896 inp->inp_laddr = laddr;
897 in_pcbrehash(inp);
898
899 /* Compute window scaling to request. */
900 while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
901 (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat)
902 tp->request_r_scale++;
903
904 soisconnecting(so);
905 tcpstat.tcps_connattempt++;
906 tp->t_state = TCPS_SYN_SENT;
907 callout_reset(tp->tt_keep, tcp_keepinit, tcp_timer_keep, tp);
908 tp->iss = tcp_new_isn(tp);
909 tp->t_bw_rtseq = tp->iss;
910 tcp_sendseqinit(tp);
911
912 /*
913 * Generate a CC value for this connection and
914 * check whether CC or CCnew should be used.
915 */
916 if (tcp_do_rfc1644)
917 tcp_hc_gettao(&inp->inp_inc, &tao);
918
919 tp->cc_send = CC_INC(tcp_ccgen);
920 if (tao.tao_ccsent != 0 &&
921 CC_GEQ(tp->cc_send, tao.tao_ccsent)) {
922 tao.tao_ccsent = tp->cc_send;
923 } else {
924 tao.tao_ccsent = 0;
925 tp->t_flags |= TF_SENDCCNEW;
926 }
927
928 if (tcp_do_rfc1644)
929 tcp_hc_updatetao(&inp->inp_inc, TCP_HC_TAO_CCSENT,
930 tao.tao_ccsent, 0);
931
932 return 0;
933}
934
935#ifdef INET6
936static int
937tcp6_connect(tp, nam, td)
938 register struct tcpcb *tp;
939 struct sockaddr *nam;
940 struct thread *td;
941{
942 struct inpcb *inp = tp->t_inpcb, *oinp;
943 struct socket *so = inp->inp_socket;
944 struct tcptw *otw;
945 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
946 struct in6_addr *addr6;
947 struct rmxp_tao tao;
948 int error;
949
950 bzero(&tao, sizeof(tao));
951
952 if (inp->inp_lport == 0) {
953 error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
954 if (error)
955 return error;
956 }
957
958 /*
959 * Cannot simply call in_pcbconnect, because there might be an
960 * earlier incarnation of this same connection still in
961 * TIME_WAIT state, creating an ADDRINUSE error.
962 */
963 error = in6_pcbladdr(inp, nam, &addr6);
964 if (error)
965 return error;
966 oinp = in6_pcblookup_hash(inp->inp_pcbinfo,
967 &sin6->sin6_addr, sin6->sin6_port,
968 IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)
969 ? addr6
970 : &inp->in6p_laddr,
971 inp->inp_lport, 0, NULL);
972 if (oinp) {
973 if (oinp != inp &&
974 (oinp->inp_vflag & INP_TIMEWAIT) &&
975 (ticks - (otw = intotw(oinp))->t_starttime) < tcp_msl &&
976 otw->cc_recv != 0) {
977 inp->inp_faddr = oinp->inp_faddr;
978 inp->inp_fport = oinp->inp_fport;
979 (void) tcp_twclose(otw, 0);
980 } else
981 return EADDRINUSE;
982 }
983 if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr))
984 inp->in6p_laddr = *addr6;
985 inp->in6p_faddr = sin6->sin6_addr;
986 inp->inp_fport = sin6->sin6_port;
987 if ((sin6->sin6_flowinfo & IPV6_FLOWINFO_MASK) != 0)
988 inp->in6p_flowinfo = sin6->sin6_flowinfo;
989 in_pcbrehash(inp);
990
991 /* Compute window scaling to request. */
992 while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
993 (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat)
994 tp->request_r_scale++;
995
996 soisconnecting(so);
997 tcpstat.tcps_connattempt++;
998 tp->t_state = TCPS_SYN_SENT;
999 callout_reset(tp->tt_keep, tcp_keepinit, tcp_timer_keep, tp);
1000 tp->iss = tcp_new_isn(tp);
1001 tp->t_bw_rtseq = tp->iss;
1002 tcp_sendseqinit(tp);
1003
1004 /*
1005 * Generate a CC value for this connection and
1006 * check whether CC or CCnew should be used.
1007 */
1008 if (tcp_do_rfc1644)
1009 tcp_hc_gettao(&inp->inp_inc, &tao);
1010
1011 tp->cc_send = CC_INC(tcp_ccgen);
1012 if (tao.tao_ccsent != 0 &&
1013 CC_GEQ(tp->cc_send, tao.tao_ccsent)) {
1014 tao.tao_ccsent = tp->cc_send;
1015 } else {
1016 tao.tao_ccsent = 0;
1017 tp->t_flags |= TF_SENDCCNEW;
1018 }
1019 if (tcp_do_rfc1644)
1020 tcp_hc_updatetao(&inp->inp_inc, TCP_HC_TAO_CCSENT,
1021 tao.tao_ccsent, 0);
1022
1023 return 0;
1024}
1025#endif /* INET6 */
1026
1027/*
1028 * The new sockopt interface makes it possible for us to block in the
1029 * copyin/out step (if we take a page fault). Taking a page fault at
1030 * splnet() is probably a Bad Thing. (Since sockets and pcbs both now
1031 * use TSM, there probably isn't any need for this function to run at
1032 * splnet() any more. This needs more examination.)
1033 */
1034int
1035tcp_ctloutput(so, sopt)
1036 struct socket *so;
1037 struct sockopt *sopt;
1038{
1039 int error, opt, optval, s;
1040 struct inpcb *inp;
1041 struct tcpcb *tp;
1042
1043 error = 0;
1044 s = splnet(); /* XXX */
1045 INP_INFO_RLOCK(&tcbinfo);
1046 inp = sotoinpcb(so);
1047 if (inp == NULL) {
1048 INP_INFO_RUNLOCK(&tcbinfo);
1049 splx(s);
1050 return (ECONNRESET);
1051 }
1052 INP_LOCK(inp);
1053 INP_INFO_RUNLOCK(&tcbinfo);
1054 if (sopt->sopt_level != IPPROTO_TCP) {
1055#ifdef INET6
1056 if (INP_CHECK_SOCKAF(so, AF_INET6))
1057 error = ip6_ctloutput(so, sopt);
1058 else
1059#endif /* INET6 */
1060 error = ip_ctloutput(so, sopt);
1061 INP_UNLOCK(inp);
1062 splx(s);
1063 return (error);
1064 }
1065 tp = intotcpcb(inp);
1066
1067 switch (sopt->sopt_dir) {
1068 case SOPT_SET:
1069 switch (sopt->sopt_name) {
1070#ifdef TCP_SIGNATURE
1071 case TCP_MD5SIG:
1072 error = sooptcopyin(sopt, &optval, sizeof optval,
1073 sizeof optval);
1074 if (error)
1075 break;
1076
1077 if (optval > 0)
1078 tp->t_flags |= TF_SIGNATURE;
1079 else
1080 tp->t_flags &= ~TF_SIGNATURE;
1081 break;
1082#endif /* TCP_SIGNATURE */
1083 case TCP_NODELAY:
1084 case TCP_NOOPT:
1085 error = sooptcopyin(sopt, &optval, sizeof optval,
1086 sizeof optval);
1087 if (error)
1088 break;
1089
1090 switch (sopt->sopt_name) {
1091 case TCP_NODELAY:
1092 opt = TF_NODELAY;
1093 break;
1094 case TCP_NOOPT:
1095 opt = TF_NOOPT;
1096 break;
1097 default:
1098 opt = 0; /* dead code to fool gcc */
1099 break;
1100 }
1101
1102 if (optval)
1103 tp->t_flags |= opt;
1104 else
1105 tp->t_flags &= ~opt;
1106 break;
1107
1108 case TCP_NOPUSH:
1109 error = sooptcopyin(sopt, &optval, sizeof optval,
1110 sizeof optval);
1111 if (error)
1112 break;
1113
1114 if (optval)
1115 tp->t_flags |= TF_NOPUSH;
1116 else {
1117 tp->t_flags &= ~TF_NOPUSH;
1118 error = tcp_output(tp);
1119 }
1120 break;
1121
1122 case TCP_MAXSEG:
1123 error = sooptcopyin(sopt, &optval, sizeof optval,
1124 sizeof optval);
1125 if (error)
1126 break;
1127
1128 if (optval > 0 && optval <= tp->t_maxseg &&
1129 optval + 40 >= tcp_minmss)
1130 tp->t_maxseg = optval;
1131 else
1132 error = EINVAL;
1133 break;
1134
1135 default:
1136 error = ENOPROTOOPT;
1137 break;
1138 }
1139 break;
1140
1141 case SOPT_GET:
1142 switch (sopt->sopt_name) {
1143#ifdef TCP_SIGNATURE
1144 case TCP_MD5SIG:
1145 optval = (tp->t_flags & TF_SIGNATURE) ? 1 : 0;
1146 break;
1147#endif
1148 case TCP_NODELAY:
1149 optval = tp->t_flags & TF_NODELAY;
1150 break;
1151 case TCP_MAXSEG:
1152 optval = tp->t_maxseg;
1153 break;
1154 case TCP_NOOPT:
1155 optval = tp->t_flags & TF_NOOPT;
1156 break;
1157 case TCP_NOPUSH:
1158 optval = tp->t_flags & TF_NOPUSH;
1159 break;
1160 default:
1161 error = ENOPROTOOPT;
1162 break;
1163 }
1164 if (error == 0)
1165 error = sooptcopyout(sopt, &optval, sizeof optval);
1166 break;
1167 }
1168 INP_UNLOCK(inp);
1169 splx(s);
1170 return (error);
1171}
1172
1173/*
1174 * tcp_sendspace and tcp_recvspace are the default send and receive window
1175 * sizes, respectively. These are obsolescent (this information should
1176 * be set by the route).
1177 */
1178u_long tcp_sendspace = 1024*32;
1179SYSCTL_INT(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace, CTLFLAG_RW,
1180 &tcp_sendspace , 0, "Maximum outgoing TCP datagram size");
1181u_long tcp_recvspace = 1024*64;
1182SYSCTL_INT(_net_inet_tcp, TCPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
1183 &tcp_recvspace , 0, "Maximum incoming TCP datagram size");
1184
1185/*
1186 * Attach TCP protocol to socket, allocating
1187 * internet protocol control block, tcp control block,
1188 * bufer space, and entering LISTEN state if to accept connections.
1189 */
1190static int
1191tcp_attach(so, td)
1192 struct socket *so;
1193 struct thread *td;
1194{
1195 register struct tcpcb *tp;
1196 struct inpcb *inp;
1197 int error;
1198#ifdef INET6
1199 int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6) != 0;
1200#endif
1201
1202 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
1203 error = soreserve(so, tcp_sendspace, tcp_recvspace);
1204 if (error)
1205 return (error);
1206 }
1207 error = in_pcballoc(so, &tcbinfo, "tcpinp");
1208 if (error)
1209 return (error);
1210 inp = sotoinpcb(so);
1211#ifdef INET6
1212 if (isipv6) {
1213 inp->inp_vflag |= INP_IPV6;
1214 inp->in6p_hops = -1; /* use kernel default */
1215 }
1216 else
1217#endif
1218 inp->inp_vflag |= INP_IPV4;
1219 tp = tcp_newtcpcb(inp);
1220 if (tp == 0) {
1221 int nofd = so->so_state & SS_NOFDREF; /* XXX */
1222
1223 so->so_state &= ~SS_NOFDREF; /* don't free the socket yet */
1224#ifdef INET6
1225 if (isipv6)
1226 in6_pcbdetach(inp);
1227 else
1228#endif
1229 in_pcbdetach(inp);
1230 so->so_state |= nofd;
1231 return (ENOBUFS);
1232 }
1233 tp->t_state = TCPS_CLOSED;
1234 return (0);
1235}
1236
1237/*
1238 * Initiate (or continue) disconnect.
1239 * If embryonic state, just send reset (once).
1240 * If in ``let data drain'' option and linger null, just drop.
1241 * Otherwise (hard), mark socket disconnecting and drop
1242 * current input data; switch states based on user close, and
1243 * send segment to peer (with FIN).
1244 */
1245static struct tcpcb *
1246tcp_disconnect(tp)
1247 register struct tcpcb *tp;
1248{
1249 struct socket *so = tp->t_inpcb->inp_socket;
1250
1251 if (tp->t_state < TCPS_ESTABLISHED)
1252 tp = tcp_close(tp);
1253 else if ((so->so_options & SO_LINGER) && so->so_linger == 0)
1254 tp = tcp_drop(tp, 0);
1255 else {
1256 soisdisconnecting(so);
1257 sbflush(&so->so_rcv);
1258 tp = tcp_usrclosed(tp);
1259 if (tp)
1260 (void) tcp_output(tp);
1261 }
1262 return (tp);
1263}
1264
1265/*
1266 * User issued close, and wish to trail through shutdown states:
1267 * if never received SYN, just forget it. If got a SYN from peer,
1268 * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
1269 * If already got a FIN from peer, then almost done; go to LAST_ACK
1270 * state. In all other cases, have already sent FIN to peer (e.g.
1271 * after PRU_SHUTDOWN), and just have to play tedious game waiting
1272 * for peer to send FIN or not respond to keep-alives, etc.
1273 * We can let the user exit from the close as soon as the FIN is acked.
1274 */
1275static struct tcpcb *
1276tcp_usrclosed(tp)
1277 register struct tcpcb *tp;
1278{
1279
1280 switch (tp->t_state) {
1281
1282 case TCPS_CLOSED:
1283 case TCPS_LISTEN:
1284 tp->t_state = TCPS_CLOSED;
1285 tp = tcp_close(tp);
1286 break;
1287
1288 case TCPS_SYN_SENT:
1289 case TCPS_SYN_RECEIVED:
1290 tp->t_flags |= TF_NEEDFIN;
1291 break;
1292
1293 case TCPS_ESTABLISHED:
1294 tp->t_state = TCPS_FIN_WAIT_1;
1295 break;
1296
1297 case TCPS_CLOSE_WAIT:
1298 tp->t_state = TCPS_LAST_ACK;
1299 break;
1300 }
1301 if (tp && tp->t_state >= TCPS_FIN_WAIT_2) {
1302 soisdisconnected(tp->t_inpcb->inp_socket);
1303 /* To prevent the connection hanging in FIN_WAIT_2 forever. */
1304 if (tp->t_state == TCPS_FIN_WAIT_2)
1305 callout_reset(tp->tt_2msl, tcp_maxidle,
1306 tcp_timer_2msl, tp);
1307 }
1308 return (tp);
1309}
1310
2 * Copyright (c) 1982, 1986, 1988, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 * From: @(#)tcp_usrreq.c 8.2 (Berkeley) 1/3/94
34 * $FreeBSD: head/sys/netinet/tcp_usrreq.c 127505 2004-03-27 21:05:46Z pjd $
35 */
36
37#include "opt_ipsec.h"
38#include "opt_inet.h"
39#include "opt_inet6.h"
40#include "opt_tcpdebug.h"
41
42#include <sys/param.h>
43#include <sys/systm.h>
44#include <sys/malloc.h>
45#include <sys/kernel.h>
46#include <sys/sysctl.h>
47#include <sys/mbuf.h>
48#ifdef INET6
49#include <sys/domain.h>
50#endif /* INET6 */
51#include <sys/socket.h>
52#include <sys/socketvar.h>
53#include <sys/protosw.h>
54#include <sys/proc.h>
55#include <sys/jail.h>
56
57#include <net/if.h>
58#include <net/route.h>
59
60#include <netinet/in.h>
61#include <netinet/in_systm.h>
62#ifdef INET6
63#include <netinet/ip6.h>
64#endif
65#include <netinet/in_pcb.h>
66#ifdef INET6
67#include <netinet6/in6_pcb.h>
68#endif
69#include <netinet/in_var.h>
70#include <netinet/ip_var.h>
71#ifdef INET6
72#include <netinet6/ip6_var.h>
73#endif
74#include <netinet/tcp.h>
75#include <netinet/tcp_fsm.h>
76#include <netinet/tcp_seq.h>
77#include <netinet/tcp_timer.h>
78#include <netinet/tcp_var.h>
79#include <netinet/tcpip.h>
80#ifdef TCPDEBUG
81#include <netinet/tcp_debug.h>
82#endif
83
84#ifdef IPSEC
85#include <netinet6/ipsec.h>
86#endif /*IPSEC*/
87
88/*
89 * TCP protocol interface to socket abstraction.
90 */
91extern char *tcpstates[]; /* XXX ??? */
92
93static int tcp_attach(struct socket *, struct thread *td);
94static int tcp_connect(struct tcpcb *, struct sockaddr *,
95 struct thread *td);
96#ifdef INET6
97static int tcp6_connect(struct tcpcb *, struct sockaddr *,
98 struct thread *td);
99#endif /* INET6 */
100static struct tcpcb *
101 tcp_disconnect(struct tcpcb *);
102static struct tcpcb *
103 tcp_usrclosed(struct tcpcb *);
104
105#ifdef TCPDEBUG
106#define TCPDEBUG0 int ostate = 0
107#define TCPDEBUG1() ostate = tp ? tp->t_state : 0
108#define TCPDEBUG2(req) if (tp && (so->so_options & SO_DEBUG)) \
109 tcp_trace(TA_USER, ostate, tp, 0, 0, req)
110#else
111#define TCPDEBUG0
112#define TCPDEBUG1()
113#define TCPDEBUG2(req)
114#endif
115
116/*
117 * TCP attaches to socket via pru_attach(), reserving space,
118 * and an internet control block.
119 */
120static int
121tcp_usr_attach(struct socket *so, int proto, struct thread *td)
122{
123 int s = splnet();
124 int error;
125 struct inpcb *inp;
126 struct tcpcb *tp = 0;
127 TCPDEBUG0;
128
129 INP_INFO_WLOCK(&tcbinfo);
130 TCPDEBUG1();
131 inp = sotoinpcb(so);
132 if (inp) {
133 error = EISCONN;
134 goto out;
135 }
136
137 error = tcp_attach(so, td);
138 if (error)
139 goto out;
140
141 if ((so->so_options & SO_LINGER) && so->so_linger == 0)
142 so->so_linger = TCP_LINGERTIME;
143
144 inp = sotoinpcb(so);
145 tp = intotcpcb(inp);
146out:
147 TCPDEBUG2(PRU_ATTACH);
148 INP_INFO_WUNLOCK(&tcbinfo);
149 splx(s);
150 return error;
151}
152
153/*
154 * pru_detach() detaches the TCP protocol from the socket.
155 * If the protocol state is non-embryonic, then can't
156 * do this directly: have to initiate a pru_disconnect(),
157 * which may finish later; embryonic TCB's can just
158 * be discarded here.
159 */
160static int
161tcp_usr_detach(struct socket *so)
162{
163 int s = splnet();
164 int error = 0;
165 struct inpcb *inp;
166 struct tcpcb *tp;
167 TCPDEBUG0;
168
169 INP_INFO_WLOCK(&tcbinfo);
170 inp = sotoinpcb(so);
171 if (inp == 0) {
172 INP_INFO_WUNLOCK(&tcbinfo);
173 splx(s);
174 return EINVAL; /* XXX */
175 }
176 INP_LOCK(inp);
177 tp = intotcpcb(inp);
178 TCPDEBUG1();
179 tp = tcp_disconnect(tp);
180
181 TCPDEBUG2(PRU_DETACH);
182 if (tp)
183 INP_UNLOCK(inp);
184 INP_INFO_WUNLOCK(&tcbinfo);
185 splx(s);
186 return error;
187}
188
189#define INI_NOLOCK 0
190#define INI_READ 1
191#define INI_WRITE 2
192
193#define COMMON_START() \
194 TCPDEBUG0; \
195 do { \
196 if (inirw == INI_READ) \
197 INP_INFO_RLOCK(&tcbinfo); \
198 else if (inirw == INI_WRITE) \
199 INP_INFO_WLOCK(&tcbinfo); \
200 inp = sotoinpcb(so); \
201 if (inp == 0) { \
202 if (inirw == INI_READ) \
203 INP_INFO_RUNLOCK(&tcbinfo); \
204 else if (inirw == INI_WRITE) \
205 INP_INFO_WUNLOCK(&tcbinfo); \
206 splx(s); \
207 return EINVAL; \
208 } \
209 INP_LOCK(inp); \
210 if (inirw == INI_READ) \
211 INP_INFO_RUNLOCK(&tcbinfo); \
212 tp = intotcpcb(inp); \
213 TCPDEBUG1(); \
214} while(0)
215
216#define COMMON_END(req) \
217out: TCPDEBUG2(req); \
218 do { \
219 if (tp) \
220 INP_UNLOCK(inp); \
221 if (inirw == INI_WRITE) \
222 INP_INFO_WUNLOCK(&tcbinfo); \
223 splx(s); \
224 return error; \
225 goto out; \
226} while(0)
227
228/*
229 * Give the socket an address.
230 */
231static int
232tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
233{
234 int s = splnet();
235 int error = 0;
236 struct inpcb *inp;
237 struct tcpcb *tp;
238 struct sockaddr_in *sinp;
239 const int inirw = INI_WRITE;
240
241 COMMON_START();
242
243 /*
244 * Must check for multicast addresses and disallow binding
245 * to them.
246 */
247 sinp = (struct sockaddr_in *)nam;
248 if (nam->sa_len != sizeof (*sinp))
249 return (EINVAL);
250 if (sinp->sin_family == AF_INET &&
251 IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) {
252 error = EAFNOSUPPORT;
253 goto out;
254 }
255 error = in_pcbbind(inp, nam, td->td_ucred);
256 if (error)
257 goto out;
258 COMMON_END(PRU_BIND);
259}
260
261#ifdef INET6
262static int
263tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
264{
265 int s = splnet();
266 int error = 0;
267 struct inpcb *inp;
268 struct tcpcb *tp;
269 struct sockaddr_in6 *sin6p;
270 const int inirw = INI_WRITE;
271
272 COMMON_START();
273
274 /*
275 * Must check for multicast addresses and disallow binding
276 * to them.
277 */
278 sin6p = (struct sockaddr_in6 *)nam;
279 if (nam->sa_len != sizeof (*sin6p))
280 return (EINVAL);
281 if (sin6p->sin6_family == AF_INET6 &&
282 IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) {
283 error = EAFNOSUPPORT;
284 goto out;
285 }
286 inp->inp_vflag &= ~INP_IPV4;
287 inp->inp_vflag |= INP_IPV6;
288 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
289 if (IN6_IS_ADDR_UNSPECIFIED(&sin6p->sin6_addr))
290 inp->inp_vflag |= INP_IPV4;
291 else if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
292 struct sockaddr_in sin;
293
294 in6_sin6_2_sin(&sin, sin6p);
295 inp->inp_vflag |= INP_IPV4;
296 inp->inp_vflag &= ~INP_IPV6;
297 error = in_pcbbind(inp, (struct sockaddr *)&sin,
298 td->td_ucred);
299 goto out;
300 }
301 }
302 error = in6_pcbbind(inp, nam, td->td_ucred);
303 if (error)
304 goto out;
305 COMMON_END(PRU_BIND);
306}
307#endif /* INET6 */
308
309/*
310 * Prepare to accept connections.
311 */
312static int
313tcp_usr_listen(struct socket *so, struct thread *td)
314{
315 int s = splnet();
316 int error = 0;
317 struct inpcb *inp;
318 struct tcpcb *tp;
319 const int inirw = INI_WRITE;
320
321 COMMON_START();
322 if (inp->inp_lport == 0)
323 error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
324 if (error == 0)
325 tp->t_state = TCPS_LISTEN;
326 COMMON_END(PRU_LISTEN);
327}
328
329#ifdef INET6
330static int
331tcp6_usr_listen(struct socket *so, struct thread *td)
332{
333 int s = splnet();
334 int error = 0;
335 struct inpcb *inp;
336 struct tcpcb *tp;
337 const int inirw = INI_WRITE;
338
339 COMMON_START();
340 if (inp->inp_lport == 0) {
341 inp->inp_vflag &= ~INP_IPV4;
342 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
343 inp->inp_vflag |= INP_IPV4;
344 error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
345 }
346 if (error == 0)
347 tp->t_state = TCPS_LISTEN;
348 COMMON_END(PRU_LISTEN);
349}
350#endif /* INET6 */
351
352/*
353 * Initiate connection to peer.
354 * Create a template for use in transmissions on this connection.
355 * Enter SYN_SENT state, and mark socket as connecting.
356 * Start keep-alive timer, and seed output sequence space.
357 * Send initial segment on connection.
358 */
359static int
360tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
361{
362 int s = splnet();
363 int error = 0;
364 struct inpcb *inp;
365 struct tcpcb *tp;
366 struct sockaddr_in *sinp;
367 const int inirw = INI_WRITE;
368
369 COMMON_START();
370
371 /*
372 * Must disallow TCP ``connections'' to multicast addresses.
373 */
374 sinp = (struct sockaddr_in *)nam;
375 if (nam->sa_len != sizeof (*sinp))
376 return (EINVAL);
377 if (sinp->sin_family == AF_INET
378 && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) {
379 error = EAFNOSUPPORT;
380 goto out;
381 }
382
383 if (td && jailed(td->td_ucred))
384 prison_remote_ip(td->td_ucred, 0, &sinp->sin_addr.s_addr);
385
386 if ((error = tcp_connect(tp, nam, td)) != 0)
387 goto out;
388 error = tcp_output(tp);
389 COMMON_END(PRU_CONNECT);
390}
391
392#ifdef INET6
393static int
394tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
395{
396 int s = splnet();
397 int error = 0;
398 struct inpcb *inp;
399 struct tcpcb *tp;
400 struct sockaddr_in6 *sin6p;
401 const int inirw = INI_WRITE;
402
403 COMMON_START();
404
405 /*
406 * Must disallow TCP ``connections'' to multicast addresses.
407 */
408 sin6p = (struct sockaddr_in6 *)nam;
409 if (nam->sa_len != sizeof (*sin6p))
410 return (EINVAL);
411 if (sin6p->sin6_family == AF_INET6
412 && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) {
413 error = EAFNOSUPPORT;
414 goto out;
415 }
416
417 if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
418 struct sockaddr_in sin;
419
420 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
421 error = EINVAL;
422 goto out;
423 }
424
425 in6_sin6_2_sin(&sin, sin6p);
426 inp->inp_vflag |= INP_IPV4;
427 inp->inp_vflag &= ~INP_IPV6;
428 if ((error = tcp_connect(tp, (struct sockaddr *)&sin, td)) != 0)
429 goto out;
430 error = tcp_output(tp);
431 goto out;
432 }
433 inp->inp_vflag &= ~INP_IPV4;
434 inp->inp_vflag |= INP_IPV6;
435 inp->inp_inc.inc_isipv6 = 1;
436 if ((error = tcp6_connect(tp, nam, td)) != 0)
437 goto out;
438 error = tcp_output(tp);
439 COMMON_END(PRU_CONNECT);
440}
441#endif /* INET6 */
442
443/*
444 * Initiate disconnect from peer.
445 * If connection never passed embryonic stage, just drop;
446 * else if don't need to let data drain, then can just drop anyways,
447 * else have to begin TCP shutdown process: mark socket disconnecting,
448 * drain unread data, state switch to reflect user close, and
449 * send segment (e.g. FIN) to peer. Socket will be really disconnected
450 * when peer sends FIN and acks ours.
451 *
452 * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.
453 */
454static int
455tcp_usr_disconnect(struct socket *so)
456{
457 int s = splnet();
458 int error = 0;
459 struct inpcb *inp;
460 struct tcpcb *tp;
461 const int inirw = INI_WRITE;
462
463 COMMON_START();
464 tp = tcp_disconnect(tp);
465 COMMON_END(PRU_DISCONNECT);
466}
467
468/*
469 * Accept a connection. Essentially all the work is
470 * done at higher levels; just return the address
471 * of the peer, storing through addr.
472 */
473static int
474tcp_usr_accept(struct socket *so, struct sockaddr **nam)
475{
476 int s;
477 int error = 0;
478 struct inpcb *inp = NULL;
479 struct tcpcb *tp = NULL;
480 struct in_addr addr;
481 in_port_t port = 0;
482 TCPDEBUG0;
483
484 if (so->so_state & SS_ISDISCONNECTED) {
485 error = ECONNABORTED;
486 goto out;
487 }
488
489 s = splnet();
490 INP_INFO_RLOCK(&tcbinfo);
491 inp = sotoinpcb(so);
492 if (!inp) {
493 INP_INFO_RUNLOCK(&tcbinfo);
494 splx(s);
495 return (EINVAL);
496 }
497 INP_LOCK(inp);
498 INP_INFO_RUNLOCK(&tcbinfo);
499 tp = intotcpcb(inp);
500 TCPDEBUG1();
501
502 /*
503 * We inline in_setpeeraddr and COMMON_END here, so that we can
504 * copy the data of interest and defer the malloc until after we
505 * release the lock.
506 */
507 port = inp->inp_fport;
508 addr = inp->inp_faddr;
509
510out: TCPDEBUG2(PRU_ACCEPT);
511 if (tp)
512 INP_UNLOCK(inp);
513 splx(s);
514 if (error == 0)
515 *nam = in_sockaddr(port, &addr);
516 return error;
517}
518
519#ifdef INET6
520static int
521tcp6_usr_accept(struct socket *so, struct sockaddr **nam)
522{
523 int s;
524 struct inpcb *inp = NULL;
525 int error = 0;
526 struct tcpcb *tp = NULL;
527 struct in_addr addr;
528 struct in6_addr addr6;
529 in_port_t port = 0;
530 int v4 = 0;
531 TCPDEBUG0;
532
533 if (so->so_state & SS_ISDISCONNECTED) {
534 error = ECONNABORTED;
535 goto out;
536 }
537
538 s = splnet();
539 INP_INFO_RLOCK(&tcbinfo);
540 inp = sotoinpcb(so);
541 if (inp == 0) {
542 INP_INFO_RUNLOCK(&tcbinfo);
543 splx(s);
544 return (EINVAL);
545 }
546 INP_LOCK(inp);
547 INP_INFO_RUNLOCK(&tcbinfo);
548 tp = intotcpcb(inp);
549 TCPDEBUG1();
550 /*
551 * We inline in6_mapped_peeraddr and COMMON_END here, so that we can
552 * copy the data of interest and defer the malloc until after we
553 * release the lock.
554 */
555 if (inp->inp_vflag & INP_IPV4) {
556 v4 = 1;
557 port = inp->inp_fport;
558 addr = inp->inp_faddr;
559 } else {
560 port = inp->inp_fport;
561 addr6 = inp->in6p_faddr;
562 }
563
564out: TCPDEBUG2(PRU_ACCEPT);
565 if (tp)
566 INP_UNLOCK(inp);
567 splx(s);
568 if (error == 0) {
569 if (v4)
570 *nam = in6_v4mapsin6_sockaddr(port, &addr);
571 else
572 *nam = in6_sockaddr(port, &addr6);
573 }
574 return error;
575}
576#endif /* INET6 */
577
578/*
579 * This is the wrapper function for in_setsockaddr. We just pass down
580 * the pcbinfo for in_setsockaddr to lock. We don't want to do the locking
581 * here because in_setsockaddr will call malloc and can block.
582 */
583static int
584tcp_sockaddr(struct socket *so, struct sockaddr **nam)
585{
586 return (in_setsockaddr(so, nam, &tcbinfo));
587}
588
589/*
590 * This is the wrapper function for in_setpeeraddr. We just pass down
591 * the pcbinfo for in_setpeeraddr to lock.
592 */
593static int
594tcp_peeraddr(struct socket *so, struct sockaddr **nam)
595{
596 return (in_setpeeraddr(so, nam, &tcbinfo));
597}
598
599/*
600 * Mark the connection as being incapable of further output.
601 */
602static int
603tcp_usr_shutdown(struct socket *so)
604{
605 int s = splnet();
606 int error = 0;
607 struct inpcb *inp;
608 struct tcpcb *tp;
609 const int inirw = INI_WRITE;
610
611 COMMON_START();
612 socantsendmore(so);
613 tp = tcp_usrclosed(tp);
614 if (tp)
615 error = tcp_output(tp);
616 COMMON_END(PRU_SHUTDOWN);
617}
618
619/*
620 * After a receive, possibly send window update to peer.
621 */
622static int
623tcp_usr_rcvd(struct socket *so, int flags)
624{
625 int s = splnet();
626 int error = 0;
627 struct inpcb *inp;
628 struct tcpcb *tp;
629 const int inirw = INI_READ;
630
631 COMMON_START();
632 tcp_output(tp);
633 COMMON_END(PRU_RCVD);
634}
635
636/*
637 * Do a send by putting data in output queue and updating urgent
638 * marker if URG set. Possibly send more data. Unlike the other
639 * pru_*() routines, the mbuf chains are our responsibility. We
640 * must either enqueue them or free them. The other pru_* routines
641 * generally are caller-frees.
642 */
643static int
644tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
645 struct sockaddr *nam, struct mbuf *control, struct thread *td)
646{
647 int s = splnet();
648 int error = 0;
649 struct inpcb *inp;
650 struct tcpcb *tp;
651 const int inirw = INI_WRITE;
652#ifdef INET6
653 int isipv6;
654#endif
655 TCPDEBUG0;
656
657 /*
658 * Need write lock here because this function might call
659 * tcp_connect or tcp_usrclosed.
660 * We really want to have to this function upgrade from read lock
661 * to write lock. XXX
662 */
663 INP_INFO_WLOCK(&tcbinfo);
664 inp = sotoinpcb(so);
665 if (inp == NULL) {
666 /*
667 * OOPS! we lost a race, the TCP session got reset after
668 * we checked SS_CANTSENDMORE, eg: while doing uiomove or a
669 * network interrupt in the non-splnet() section of sosend().
670 */
671 if (m)
672 m_freem(m);
673 if (control)
674 m_freem(control);
675 error = ECONNRESET; /* XXX EPIPE? */
676 tp = NULL;
677 TCPDEBUG1();
678 goto out;
679 }
680 INP_LOCK(inp);
681#ifdef INET6
682 isipv6 = nam && nam->sa_family == AF_INET6;
683#endif /* INET6 */
684 tp = intotcpcb(inp);
685 TCPDEBUG1();
686 if (control) {
687 /* TCP doesn't do control messages (rights, creds, etc) */
688 if (control->m_len) {
689 m_freem(control);
690 if (m)
691 m_freem(m);
692 error = EINVAL;
693 goto out;
694 }
695 m_freem(control); /* empty control, just free it */
696 }
697 if (!(flags & PRUS_OOB)) {
698 sbappendstream(&so->so_snd, m);
699 if (nam && tp->t_state < TCPS_SYN_SENT) {
700 /*
701 * Do implied connect if not yet connected,
702 * initialize window to default value, and
703 * initialize maxseg/maxopd using peer's cached
704 * MSS.
705 */
706#ifdef INET6
707 if (isipv6)
708 error = tcp6_connect(tp, nam, td);
709 else
710#endif /* INET6 */
711 error = tcp_connect(tp, nam, td);
712 if (error)
713 goto out;
714 tp->snd_wnd = TTCP_CLIENT_SND_WND;
715 tcp_mss(tp, -1);
716 }
717
718 if (flags & PRUS_EOF) {
719 /*
720 * Close the send side of the connection after
721 * the data is sent.
722 */
723 socantsendmore(so);
724 tp = tcp_usrclosed(tp);
725 }
726 if (tp != NULL) {
727 if (flags & PRUS_MORETOCOME)
728 tp->t_flags |= TF_MORETOCOME;
729 error = tcp_output(tp);
730 if (flags & PRUS_MORETOCOME)
731 tp->t_flags &= ~TF_MORETOCOME;
732 }
733 } else {
734 if (sbspace(&so->so_snd) < -512) {
735 m_freem(m);
736 error = ENOBUFS;
737 goto out;
738 }
739 /*
740 * According to RFC961 (Assigned Protocols),
741 * the urgent pointer points to the last octet
742 * of urgent data. We continue, however,
743 * to consider it to indicate the first octet
744 * of data past the urgent section.
745 * Otherwise, snd_up should be one lower.
746 */
747 sbappendstream(&so->so_snd, m);
748 if (nam && tp->t_state < TCPS_SYN_SENT) {
749 /*
750 * Do implied connect if not yet connected,
751 * initialize window to default value, and
752 * initialize maxseg/maxopd using peer's cached
753 * MSS.
754 */
755#ifdef INET6
756 if (isipv6)
757 error = tcp6_connect(tp, nam, td);
758 else
759#endif /* INET6 */
760 error = tcp_connect(tp, nam, td);
761 if (error)
762 goto out;
763 tp->snd_wnd = TTCP_CLIENT_SND_WND;
764 tcp_mss(tp, -1);
765 }
766 tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
767 tp->t_force = 1;
768 error = tcp_output(tp);
769 tp->t_force = 0;
770 }
771 COMMON_END((flags & PRUS_OOB) ? PRU_SENDOOB :
772 ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
773}
774
775/*
776 * Abort the TCP.
777 */
778static int
779tcp_usr_abort(struct socket *so)
780{
781 int s = splnet();
782 int error = 0;
783 struct inpcb *inp;
784 struct tcpcb *tp;
785 const int inirw = INI_WRITE;
786
787 COMMON_START();
788 tp = tcp_drop(tp, ECONNABORTED);
789 COMMON_END(PRU_ABORT);
790}
791
792/*
793 * Receive out-of-band data.
794 */
795static int
796tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags)
797{
798 int s = splnet();
799 int error = 0;
800 struct inpcb *inp;
801 struct tcpcb *tp;
802 const int inirw = INI_READ;
803
804 COMMON_START();
805 if ((so->so_oobmark == 0 &&
806 (so->so_state & SS_RCVATMARK) == 0) ||
807 so->so_options & SO_OOBINLINE ||
808 tp->t_oobflags & TCPOOB_HADDATA) {
809 error = EINVAL;
810 goto out;
811 }
812 if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
813 error = EWOULDBLOCK;
814 goto out;
815 }
816 m->m_len = 1;
817 *mtod(m, caddr_t) = tp->t_iobc;
818 if ((flags & MSG_PEEK) == 0)
819 tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
820 COMMON_END(PRU_RCVOOB);
821}
822
823/* xxx - should be const */
824struct pr_usrreqs tcp_usrreqs = {
825 tcp_usr_abort, tcp_usr_accept, tcp_usr_attach, tcp_usr_bind,
826 tcp_usr_connect, pru_connect2_notsupp, in_control, tcp_usr_detach,
827 tcp_usr_disconnect, tcp_usr_listen, tcp_peeraddr, tcp_usr_rcvd,
828 tcp_usr_rcvoob, tcp_usr_send, pru_sense_null, tcp_usr_shutdown,
829 tcp_sockaddr, sosend, soreceive, sopoll, in_pcbsosetlabel
830};
831
832#ifdef INET6
833struct pr_usrreqs tcp6_usrreqs = {
834 tcp_usr_abort, tcp6_usr_accept, tcp_usr_attach, tcp6_usr_bind,
835 tcp6_usr_connect, pru_connect2_notsupp, in6_control, tcp_usr_detach,
836 tcp_usr_disconnect, tcp6_usr_listen, in6_mapped_peeraddr, tcp_usr_rcvd,
837 tcp_usr_rcvoob, tcp_usr_send, pru_sense_null, tcp_usr_shutdown,
838 in6_mapped_sockaddr, sosend, soreceive, sopoll, in_pcbsosetlabel
839};
840#endif /* INET6 */
841
842/*
843 * Common subroutine to open a TCP connection to remote host specified
844 * by struct sockaddr_in in mbuf *nam. Call in_pcbbind to assign a local
845 * port number if needed. Call in_pcbconnect_setup to do the routing and
846 * to choose a local host address (interface). If there is an existing
847 * incarnation of the same connection in TIME-WAIT state and if the remote
848 * host was sending CC options and if the connection duration was < MSL, then
849 * truncate the previous TIME-WAIT state and proceed.
850 * Initialize connection parameters and enter SYN-SENT state.
851 */
852static int
853tcp_connect(tp, nam, td)
854 register struct tcpcb *tp;
855 struct sockaddr *nam;
856 struct thread *td;
857{
858 struct inpcb *inp = tp->t_inpcb, *oinp;
859 struct socket *so = inp->inp_socket;
860 struct tcptw *otw;
861 struct rmxp_tao tao;
862 struct in_addr laddr;
863 u_short lport;
864 int error;
865
866 bzero(&tao, sizeof(tao));
867
868 if (inp->inp_lport == 0) {
869 error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
870 if (error)
871 return error;
872 }
873
874 /*
875 * Cannot simply call in_pcbconnect, because there might be an
876 * earlier incarnation of this same connection still in
877 * TIME_WAIT state, creating an ADDRINUSE error.
878 */
879 laddr = inp->inp_laddr;
880 lport = inp->inp_lport;
881 error = in_pcbconnect_setup(inp, nam, &laddr.s_addr, &lport,
882 &inp->inp_faddr.s_addr, &inp->inp_fport, &oinp, td->td_ucred);
883 if (error && oinp == NULL)
884 return error;
885 if (oinp) {
886 if (oinp != inp &&
887 (oinp->inp_vflag & INP_TIMEWAIT) &&
888 (ticks - (otw = intotw(oinp))->t_starttime) < tcp_msl &&
889 otw->cc_recv != 0) {
890 inp->inp_faddr = oinp->inp_faddr;
891 inp->inp_fport = oinp->inp_fport;
892 (void) tcp_twclose(otw, 0);
893 } else
894 return EADDRINUSE;
895 }
896 inp->inp_laddr = laddr;
897 in_pcbrehash(inp);
898
899 /* Compute window scaling to request. */
900 while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
901 (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat)
902 tp->request_r_scale++;
903
904 soisconnecting(so);
905 tcpstat.tcps_connattempt++;
906 tp->t_state = TCPS_SYN_SENT;
907 callout_reset(tp->tt_keep, tcp_keepinit, tcp_timer_keep, tp);
908 tp->iss = tcp_new_isn(tp);
909 tp->t_bw_rtseq = tp->iss;
910 tcp_sendseqinit(tp);
911
912 /*
913 * Generate a CC value for this connection and
914 * check whether CC or CCnew should be used.
915 */
916 if (tcp_do_rfc1644)
917 tcp_hc_gettao(&inp->inp_inc, &tao);
918
919 tp->cc_send = CC_INC(tcp_ccgen);
920 if (tao.tao_ccsent != 0 &&
921 CC_GEQ(tp->cc_send, tao.tao_ccsent)) {
922 tao.tao_ccsent = tp->cc_send;
923 } else {
924 tao.tao_ccsent = 0;
925 tp->t_flags |= TF_SENDCCNEW;
926 }
927
928 if (tcp_do_rfc1644)
929 tcp_hc_updatetao(&inp->inp_inc, TCP_HC_TAO_CCSENT,
930 tao.tao_ccsent, 0);
931
932 return 0;
933}
934
935#ifdef INET6
936static int
937tcp6_connect(tp, nam, td)
938 register struct tcpcb *tp;
939 struct sockaddr *nam;
940 struct thread *td;
941{
942 struct inpcb *inp = tp->t_inpcb, *oinp;
943 struct socket *so = inp->inp_socket;
944 struct tcptw *otw;
945 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
946 struct in6_addr *addr6;
947 struct rmxp_tao tao;
948 int error;
949
950 bzero(&tao, sizeof(tao));
951
952 if (inp->inp_lport == 0) {
953 error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
954 if (error)
955 return error;
956 }
957
958 /*
959 * Cannot simply call in_pcbconnect, because there might be an
960 * earlier incarnation of this same connection still in
961 * TIME_WAIT state, creating an ADDRINUSE error.
962 */
963 error = in6_pcbladdr(inp, nam, &addr6);
964 if (error)
965 return error;
966 oinp = in6_pcblookup_hash(inp->inp_pcbinfo,
967 &sin6->sin6_addr, sin6->sin6_port,
968 IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)
969 ? addr6
970 : &inp->in6p_laddr,
971 inp->inp_lport, 0, NULL);
972 if (oinp) {
973 if (oinp != inp &&
974 (oinp->inp_vflag & INP_TIMEWAIT) &&
975 (ticks - (otw = intotw(oinp))->t_starttime) < tcp_msl &&
976 otw->cc_recv != 0) {
977 inp->inp_faddr = oinp->inp_faddr;
978 inp->inp_fport = oinp->inp_fport;
979 (void) tcp_twclose(otw, 0);
980 } else
981 return EADDRINUSE;
982 }
983 if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr))
984 inp->in6p_laddr = *addr6;
985 inp->in6p_faddr = sin6->sin6_addr;
986 inp->inp_fport = sin6->sin6_port;
987 if ((sin6->sin6_flowinfo & IPV6_FLOWINFO_MASK) != 0)
988 inp->in6p_flowinfo = sin6->sin6_flowinfo;
989 in_pcbrehash(inp);
990
991 /* Compute window scaling to request. */
992 while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
993 (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat)
994 tp->request_r_scale++;
995
996 soisconnecting(so);
997 tcpstat.tcps_connattempt++;
998 tp->t_state = TCPS_SYN_SENT;
999 callout_reset(tp->tt_keep, tcp_keepinit, tcp_timer_keep, tp);
1000 tp->iss = tcp_new_isn(tp);
1001 tp->t_bw_rtseq = tp->iss;
1002 tcp_sendseqinit(tp);
1003
1004 /*
1005 * Generate a CC value for this connection and
1006 * check whether CC or CCnew should be used.
1007 */
1008 if (tcp_do_rfc1644)
1009 tcp_hc_gettao(&inp->inp_inc, &tao);
1010
1011 tp->cc_send = CC_INC(tcp_ccgen);
1012 if (tao.tao_ccsent != 0 &&
1013 CC_GEQ(tp->cc_send, tao.tao_ccsent)) {
1014 tao.tao_ccsent = tp->cc_send;
1015 } else {
1016 tao.tao_ccsent = 0;
1017 tp->t_flags |= TF_SENDCCNEW;
1018 }
1019 if (tcp_do_rfc1644)
1020 tcp_hc_updatetao(&inp->inp_inc, TCP_HC_TAO_CCSENT,
1021 tao.tao_ccsent, 0);
1022
1023 return 0;
1024}
1025#endif /* INET6 */
1026
1027/*
1028 * The new sockopt interface makes it possible for us to block in the
1029 * copyin/out step (if we take a page fault). Taking a page fault at
1030 * splnet() is probably a Bad Thing. (Since sockets and pcbs both now
1031 * use TSM, there probably isn't any need for this function to run at
1032 * splnet() any more. This needs more examination.)
1033 */
1034int
1035tcp_ctloutput(so, sopt)
1036 struct socket *so;
1037 struct sockopt *sopt;
1038{
1039 int error, opt, optval, s;
1040 struct inpcb *inp;
1041 struct tcpcb *tp;
1042
1043 error = 0;
1044 s = splnet(); /* XXX */
1045 INP_INFO_RLOCK(&tcbinfo);
1046 inp = sotoinpcb(so);
1047 if (inp == NULL) {
1048 INP_INFO_RUNLOCK(&tcbinfo);
1049 splx(s);
1050 return (ECONNRESET);
1051 }
1052 INP_LOCK(inp);
1053 INP_INFO_RUNLOCK(&tcbinfo);
1054 if (sopt->sopt_level != IPPROTO_TCP) {
1055#ifdef INET6
1056 if (INP_CHECK_SOCKAF(so, AF_INET6))
1057 error = ip6_ctloutput(so, sopt);
1058 else
1059#endif /* INET6 */
1060 error = ip_ctloutput(so, sopt);
1061 INP_UNLOCK(inp);
1062 splx(s);
1063 return (error);
1064 }
1065 tp = intotcpcb(inp);
1066
1067 switch (sopt->sopt_dir) {
1068 case SOPT_SET:
1069 switch (sopt->sopt_name) {
1070#ifdef TCP_SIGNATURE
1071 case TCP_MD5SIG:
1072 error = sooptcopyin(sopt, &optval, sizeof optval,
1073 sizeof optval);
1074 if (error)
1075 break;
1076
1077 if (optval > 0)
1078 tp->t_flags |= TF_SIGNATURE;
1079 else
1080 tp->t_flags &= ~TF_SIGNATURE;
1081 break;
1082#endif /* TCP_SIGNATURE */
1083 case TCP_NODELAY:
1084 case TCP_NOOPT:
1085 error = sooptcopyin(sopt, &optval, sizeof optval,
1086 sizeof optval);
1087 if (error)
1088 break;
1089
1090 switch (sopt->sopt_name) {
1091 case TCP_NODELAY:
1092 opt = TF_NODELAY;
1093 break;
1094 case TCP_NOOPT:
1095 opt = TF_NOOPT;
1096 break;
1097 default:
1098 opt = 0; /* dead code to fool gcc */
1099 break;
1100 }
1101
1102 if (optval)
1103 tp->t_flags |= opt;
1104 else
1105 tp->t_flags &= ~opt;
1106 break;
1107
1108 case TCP_NOPUSH:
1109 error = sooptcopyin(sopt, &optval, sizeof optval,
1110 sizeof optval);
1111 if (error)
1112 break;
1113
1114 if (optval)
1115 tp->t_flags |= TF_NOPUSH;
1116 else {
1117 tp->t_flags &= ~TF_NOPUSH;
1118 error = tcp_output(tp);
1119 }
1120 break;
1121
1122 case TCP_MAXSEG:
1123 error = sooptcopyin(sopt, &optval, sizeof optval,
1124 sizeof optval);
1125 if (error)
1126 break;
1127
1128 if (optval > 0 && optval <= tp->t_maxseg &&
1129 optval + 40 >= tcp_minmss)
1130 tp->t_maxseg = optval;
1131 else
1132 error = EINVAL;
1133 break;
1134
1135 default:
1136 error = ENOPROTOOPT;
1137 break;
1138 }
1139 break;
1140
1141 case SOPT_GET:
1142 switch (sopt->sopt_name) {
1143#ifdef TCP_SIGNATURE
1144 case TCP_MD5SIG:
1145 optval = (tp->t_flags & TF_SIGNATURE) ? 1 : 0;
1146 break;
1147#endif
1148 case TCP_NODELAY:
1149 optval = tp->t_flags & TF_NODELAY;
1150 break;
1151 case TCP_MAXSEG:
1152 optval = tp->t_maxseg;
1153 break;
1154 case TCP_NOOPT:
1155 optval = tp->t_flags & TF_NOOPT;
1156 break;
1157 case TCP_NOPUSH:
1158 optval = tp->t_flags & TF_NOPUSH;
1159 break;
1160 default:
1161 error = ENOPROTOOPT;
1162 break;
1163 }
1164 if (error == 0)
1165 error = sooptcopyout(sopt, &optval, sizeof optval);
1166 break;
1167 }
1168 INP_UNLOCK(inp);
1169 splx(s);
1170 return (error);
1171}
1172
1173/*
1174 * tcp_sendspace and tcp_recvspace are the default send and receive window
1175 * sizes, respectively. These are obsolescent (this information should
1176 * be set by the route).
1177 */
1178u_long tcp_sendspace = 1024*32;
1179SYSCTL_INT(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace, CTLFLAG_RW,
1180 &tcp_sendspace , 0, "Maximum outgoing TCP datagram size");
1181u_long tcp_recvspace = 1024*64;
1182SYSCTL_INT(_net_inet_tcp, TCPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
1183 &tcp_recvspace , 0, "Maximum incoming TCP datagram size");
1184
1185/*
1186 * Attach TCP protocol to socket, allocating
1187 * internet protocol control block, tcp control block,
1188 * bufer space, and entering LISTEN state if to accept connections.
1189 */
1190static int
1191tcp_attach(so, td)
1192 struct socket *so;
1193 struct thread *td;
1194{
1195 register struct tcpcb *tp;
1196 struct inpcb *inp;
1197 int error;
1198#ifdef INET6
1199 int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6) != 0;
1200#endif
1201
1202 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
1203 error = soreserve(so, tcp_sendspace, tcp_recvspace);
1204 if (error)
1205 return (error);
1206 }
1207 error = in_pcballoc(so, &tcbinfo, "tcpinp");
1208 if (error)
1209 return (error);
1210 inp = sotoinpcb(so);
1211#ifdef INET6
1212 if (isipv6) {
1213 inp->inp_vflag |= INP_IPV6;
1214 inp->in6p_hops = -1; /* use kernel default */
1215 }
1216 else
1217#endif
1218 inp->inp_vflag |= INP_IPV4;
1219 tp = tcp_newtcpcb(inp);
1220 if (tp == 0) {
1221 int nofd = so->so_state & SS_NOFDREF; /* XXX */
1222
1223 so->so_state &= ~SS_NOFDREF; /* don't free the socket yet */
1224#ifdef INET6
1225 if (isipv6)
1226 in6_pcbdetach(inp);
1227 else
1228#endif
1229 in_pcbdetach(inp);
1230 so->so_state |= nofd;
1231 return (ENOBUFS);
1232 }
1233 tp->t_state = TCPS_CLOSED;
1234 return (0);
1235}
1236
1237/*
1238 * Initiate (or continue) disconnect.
1239 * If embryonic state, just send reset (once).
1240 * If in ``let data drain'' option and linger null, just drop.
1241 * Otherwise (hard), mark socket disconnecting and drop
1242 * current input data; switch states based on user close, and
1243 * send segment to peer (with FIN).
1244 */
1245static struct tcpcb *
1246tcp_disconnect(tp)
1247 register struct tcpcb *tp;
1248{
1249 struct socket *so = tp->t_inpcb->inp_socket;
1250
1251 if (tp->t_state < TCPS_ESTABLISHED)
1252 tp = tcp_close(tp);
1253 else if ((so->so_options & SO_LINGER) && so->so_linger == 0)
1254 tp = tcp_drop(tp, 0);
1255 else {
1256 soisdisconnecting(so);
1257 sbflush(&so->so_rcv);
1258 tp = tcp_usrclosed(tp);
1259 if (tp)
1260 (void) tcp_output(tp);
1261 }
1262 return (tp);
1263}
1264
1265/*
1266 * User issued close, and wish to trail through shutdown states:
1267 * if never received SYN, just forget it. If got a SYN from peer,
1268 * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
1269 * If already got a FIN from peer, then almost done; go to LAST_ACK
1270 * state. In all other cases, have already sent FIN to peer (e.g.
1271 * after PRU_SHUTDOWN), and just have to play tedious game waiting
1272 * for peer to send FIN or not respond to keep-alives, etc.
1273 * We can let the user exit from the close as soon as the FIN is acked.
1274 */
1275static struct tcpcb *
1276tcp_usrclosed(tp)
1277 register struct tcpcb *tp;
1278{
1279
1280 switch (tp->t_state) {
1281
1282 case TCPS_CLOSED:
1283 case TCPS_LISTEN:
1284 tp->t_state = TCPS_CLOSED;
1285 tp = tcp_close(tp);
1286 break;
1287
1288 case TCPS_SYN_SENT:
1289 case TCPS_SYN_RECEIVED:
1290 tp->t_flags |= TF_NEEDFIN;
1291 break;
1292
1293 case TCPS_ESTABLISHED:
1294 tp->t_state = TCPS_FIN_WAIT_1;
1295 break;
1296
1297 case TCPS_CLOSE_WAIT:
1298 tp->t_state = TCPS_LAST_ACK;
1299 break;
1300 }
1301 if (tp && tp->t_state >= TCPS_FIN_WAIT_2) {
1302 soisdisconnected(tp->t_inpcb->inp_socket);
1303 /* To prevent the connection hanging in FIN_WAIT_2 forever. */
1304 if (tp->t_state == TCPS_FIN_WAIT_2)
1305 callout_reset(tp->tt_2msl, tcp_maxidle,
1306 tcp_timer_2msl, tp);
1307 }
1308 return (tp);
1309}
1310