2 * Copyright (c) 2003, 2004 Jeffrey M. Hsu. All rights reserved.
3 * Copyright (c) 2003, 2004 The DragonFly Project. All rights reserved.
5 * This code is derived from software contributed to The DragonFly Project
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62 * From: @(#)tcp_usrreq.c 8.2 (Berkeley) 1/3/94
63 * $FreeBSD: src/sys/netinet/tcp_usrreq.c,v 1.51.2.17 2002/10/11 11:46:44 ume Exp $
66 #include "opt_ipsec.h"
68 #include "opt_inet6.h"
69 #include "opt_tcpdebug.h"
71 #include <sys/param.h>
72 #include <sys/systm.h>
73 #include <sys/kernel.h>
74 #include <sys/malloc.h>
75 #include <sys/sysctl.h>
76 #include <sys/globaldata.h>
77 #include <sys/thread.h>
81 #include <sys/domain.h>
83 #include <sys/socket.h>
84 #include <sys/socketvar.h>
85 #include <sys/socketops.h>
86 #include <sys/protosw.h>
88 #include <sys/thread2.h>
89 #include <sys/msgport2.h>
90 #include <sys/socketvar2.h>
93 #include <net/netisr.h>
94 #include <net/route.h>
96 #include <net/netmsg2.h>
97 #include <net/netisr2.h>
99 #include <netinet/in.h>
100 #include <netinet/in_systm.h>
102 #include <netinet/ip6.h>
104 #include <netinet/in_pcb.h>
106 #include <netinet6/in6_pcb.h>
108 #include <netinet/in_var.h>
109 #include <netinet/ip_var.h>
111 #include <netinet6/ip6_var.h>
112 #include <netinet6/tcp6_var.h>
114 #include <netinet/tcp.h>
115 #include <netinet/tcp_fsm.h>
116 #include <netinet/tcp_seq.h>
117 #include <netinet/tcp_timer.h>
118 #include <netinet/tcp_timer2.h>
119 #include <netinet/tcp_var.h>
120 #include <netinet/tcpip.h>
122 #include <netinet/tcp_debug.h>
126 #include <netinet6/ipsec.h>
130 * TCP protocol interface to socket abstraction.
132 extern char *tcpstates[]; /* XXX ??? */
134 static int tcp_attach (struct socket *, struct pru_attach_info *);
135 static void tcp_connect (netmsg_t msg);
137 static void tcp6_connect (netmsg_t msg);
138 static int tcp6_connect_oncpu(struct tcpcb *tp, int flags,
140 struct sockaddr_in6 *sin6,
141 struct in6_addr *addr6);
143 static struct tcpcb *
144 tcp_disconnect (struct tcpcb *);
145 static struct tcpcb *
146 tcp_usrclosed (struct tcpcb *);
149 #define TCPDEBUG0 int ostate = 0
150 #define TCPDEBUG1() ostate = tp ? tp->t_state : 0
151 #define TCPDEBUG2(req) if (tp && (so->so_options & SO_DEBUG)) \
152 tcp_trace(TA_USER, ostate, tp, 0, 0, req)
156 #define TCPDEBUG2(req)
159 static int tcp_lport_extension = 1;
160 SYSCTL_INT(_net_inet_tcp, OID_AUTO, lportext, CTLFLAG_RW,
161 &tcp_lport_extension, 0, "");
164 * For some ill optimized programs, which try to use TCP_NOPUSH
165 * to improve performance, will have small amount of data sits
166 * in the sending buffer. These small amount of data will _not_
167 * be pushed into the network until more data are written into
168 * the socket or the socket write side is shutdown.
170 static int tcp_disable_nopush = 1;
171 SYSCTL_INT(_net_inet_tcp, OID_AUTO, disable_nopush, CTLFLAG_RW,
172 &tcp_disable_nopush, 0, "TCP_NOPUSH socket option will have no effect");
175 * Allocate socket buffer space.
178 tcp_usr_preattach(struct socket *so, int proto __unused,
179 struct pru_attach_info *ai)
183 if (so->so_snd.ssb_hiwat == 0 || so->so_rcv.ssb_hiwat == 0) {
184 error = soreserve(so, tcp_sendspace, tcp_recvspace,
189 atomic_set_int(&so->so_rcv.ssb_flags, SSB_AUTOSIZE | SSB_PREALLOC);
190 atomic_set_int(&so->so_snd.ssb_flags, SSB_AUTOSIZE | SSB_PREALLOC);
196 * TCP attaches to socket via pru_attach(), reserving space,
197 * and an internet control block. This socket may move to
198 * other CPU later when we bind/connect.
201 tcp_usr_attach(netmsg_t msg)
203 struct socket *so = msg->base.nm_so;
204 struct pru_attach_info *ai = msg->attach.nm_ai;
207 struct tcpcb *tp = NULL;
218 error = tcp_attach(so, ai);
222 if ((so->so_options & SO_LINGER) && so->so_linger == 0)
223 so->so_linger = TCP_LINGERTIME;
226 sofree(so); /* from ref above */
227 TCPDEBUG2(PRU_ATTACH);
228 lwkt_replymsg(&msg->lmsg, error);
232 * pru_detach() detaches the TCP protocol from the socket.
233 * If the protocol state is non-embryonic, then can't
234 * do this directly: have to initiate a pru_disconnect(),
235 * which may finish later; embryonic TCB's can just
239 tcp_usr_detach(netmsg_t msg)
241 struct socket *so = msg->base.nm_so;
250 * If the inp is already detached or never attached, it may have
251 * been due to an async close or async attach failure. Just return
252 * as if no error occured.
254 * It's possible for the tcpcb (tp) to disconnect from the inp due
255 * to tcp_drop()->tcp_close() being called. This may occur *after*
256 * the detach message has been queued so we may find a NULL tp here.
259 if ((tp = intotcpcb(inp)) != NULL) {
261 tp = tcp_disconnect(tp);
262 TCPDEBUG2(PRU_DETACH);
265 lwkt_replymsg(&msg->lmsg, error);
269 * NOTE: ignore_error is non-zero for certain disconnection races
270 * which we want to silently allow, otherwise close() may return
271 * an unexpected error.
273 * NOTE: The variables (msg) and (tp) are assumed.
275 #define COMMON_START(so, inp, ignore_error) \
281 error = ignore_error ? 0 : EINVAL; \
285 tp = intotcpcb(inp); \
289 #define COMMON_END1(req, noreply) \
293 lwkt_replymsg(&msg->lmsg, error); \
297 #define COMMON_END(req) COMMON_END1((req), 0)
300 * Give the socket an address.
303 tcp_usr_bind(netmsg_t msg)
305 struct socket *so = msg->bind.base.nm_so;
306 struct sockaddr *nam = msg->bind.nm_nam;
307 struct thread *td = msg->bind.nm_td;
311 struct sockaddr_in *sinp;
313 COMMON_START(so, inp, 0);
316 * Must check for multicast addresses and disallow binding
319 sinp = (struct sockaddr_in *)nam;
320 if (sinp->sin_family == AF_INET &&
321 IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) {
322 error = EAFNOSUPPORT;
325 error = in_pcbbind(inp, nam, td);
329 COMMON_END(PRU_BIND);
335 tcp6_usr_bind(netmsg_t msg)
337 struct socket *so = msg->bind.base.nm_so;
338 struct sockaddr *nam = msg->bind.nm_nam;
339 struct thread *td = msg->bind.nm_td;
343 struct sockaddr_in6 *sin6p;
345 COMMON_START(so, inp, 0);
348 * Must check for multicast addresses and disallow binding
351 sin6p = (struct sockaddr_in6 *)nam;
352 if (sin6p->sin6_family == AF_INET6 &&
353 IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) {
354 error = EAFNOSUPPORT;
357 error = in6_pcbbind(inp, nam, td);
360 COMMON_END(PRU_BIND);
364 struct netmsg_inswildcard {
365 struct netmsg_base base;
366 struct inpcb *nm_inp;
370 in_pcbinswildcardhash_handler(netmsg_t msg)
372 struct netmsg_inswildcard *nm = (struct netmsg_inswildcard *)msg;
373 int cpu = mycpuid, nextcpu;
375 in_pcbinswildcardhash_oncpu(nm->nm_inp, &tcbinfo[cpu]);
378 if (nextcpu < ncpus2)
379 lwkt_forwardmsg(netisr_cpuport(nextcpu), &nm->base.lmsg);
381 lwkt_replymsg(&nm->base.lmsg, 0);
385 tcp_sosetport(struct lwkt_msg *msg, lwkt_port_t port)
387 sosetport(((struct netmsg_base *)msg)->nm_so, port);
391 * Prepare to accept connections.
394 tcp_usr_listen(netmsg_t msg)
396 struct socket *so = msg->listen.base.nm_so;
397 struct thread *td = msg->listen.nm_td;
401 struct netmsg_inswildcard nm;
402 lwkt_port_t port0 = netisr_cpuport(0);
404 COMMON_START(so, inp, 0);
406 if (&curthread->td_msgport != port0) {
407 lwkt_msg_t lmsg = &msg->listen.base.lmsg;
409 KASSERT((msg->listen.nm_flags & PRUL_RELINK) == 0,
410 ("already asked to relink"));
412 in_pcbunlink(so->so_pcb, &tcbinfo[mycpuid]);
413 msg->listen.nm_flags |= PRUL_RELINK;
415 /* See the related comment in tcp_connect() */
416 lwkt_setmsg_receipt(lmsg, tcp_sosetport);
417 lwkt_forwardmsg(port0, lmsg);
418 /* msg invalid now */
421 KASSERT(so->so_port == port0, ("so_port is not netisr0"));
423 if (msg->listen.nm_flags & PRUL_RELINK) {
424 msg->listen.nm_flags &= ~PRUL_RELINK;
425 in_pcblink(so->so_pcb, &tcbinfo[mycpuid]);
427 KASSERT(inp->inp_pcbinfo == &tcbinfo[0], ("pcbinfo is not tcbinfo0"));
429 if (tp->t_flags & TF_LISTEN)
432 if (inp->inp_lport == 0) {
433 error = in_pcbbind(inp, NULL, td);
438 tp->t_state = TCPS_LISTEN;
439 tp->t_flags |= TF_LISTEN;
440 tp->tt_msg = NULL; /* Catch any invalid timer usage */
444 * Put this inpcb into wildcard hash on other cpus.
446 ASSERT_INP_NOTINHASH(inp);
447 netmsg_init(&nm.base, NULL, &curthread->td_msgport,
448 MSGF_PRIORITY, in_pcbinswildcardhash_handler);
450 lwkt_domsg(netisr_cpuport(1), &nm.base.lmsg, 0);
452 in_pcbinswildcardhash(inp);
453 COMMON_END(PRU_LISTEN);
459 tcp6_usr_listen(netmsg_t msg)
461 struct socket *so = msg->listen.base.nm_so;
462 struct thread *td = msg->listen.nm_td;
466 struct netmsg_inswildcard nm;
468 COMMON_START(so, inp, 0);
470 if (tp->t_flags & TF_LISTEN)
473 if (inp->inp_lport == 0) {
474 error = in6_pcbbind(inp, NULL, td);
479 tp->t_state = TCPS_LISTEN;
480 tp->t_flags |= TF_LISTEN;
481 tp->tt_msg = NULL; /* Catch any invalid timer usage */
485 * Put this inpcb into wildcard hash on other cpus.
487 KKASSERT(so->so_port == netisr_cpuport(0));
489 KKASSERT(inp->inp_pcbinfo == &tcbinfo[0]);
490 ASSERT_INP_NOTINHASH(inp);
492 netmsg_init(&nm.base, NULL, &curthread->td_msgport,
493 MSGF_PRIORITY, in_pcbinswildcardhash_handler);
495 lwkt_domsg(netisr_cpuport(1), &nm.base.lmsg, 0);
497 in_pcbinswildcardhash(inp);
498 COMMON_END(PRU_LISTEN);
503 * Initiate connection to peer.
504 * Create a template for use in transmissions on this connection.
505 * Enter SYN_SENT state, and mark socket as connecting.
506 * Start keep-alive timer, and seed output sequence space.
507 * Send initial segment on connection.
510 tcp_usr_connect(netmsg_t msg)
512 struct socket *so = msg->connect.base.nm_so;
513 struct sockaddr *nam = msg->connect.nm_nam;
514 struct thread *td = msg->connect.nm_td;
518 struct sockaddr_in *sinp;
520 COMMON_START(so, inp, 0);
523 * Must disallow TCP ``connections'' to multicast addresses.
525 sinp = (struct sockaddr_in *)nam;
526 if (sinp->sin_family == AF_INET
527 && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) {
528 error = EAFNOSUPPORT;
532 if (!prison_remote_ip(td, (struct sockaddr*)sinp)) {
533 error = EAFNOSUPPORT; /* IPv6 only jail */
538 /* msg is invalid now */
541 if (msg->connect.nm_m) {
542 m_freem(msg->connect.nm_m);
543 msg->connect.nm_m = NULL;
545 if (msg->connect.nm_flags & PRUC_HELDTD)
547 if (error && (msg->connect.nm_flags & PRUC_ASYNC)) {
548 so->so_error = error;
549 soisdisconnected(so);
551 lwkt_replymsg(&msg->lmsg, error);
557 tcp6_usr_connect(netmsg_t msg)
559 struct socket *so = msg->connect.base.nm_so;
560 struct sockaddr *nam = msg->connect.nm_nam;
561 struct thread *td = msg->connect.nm_td;
565 struct sockaddr_in6 *sin6p;
567 COMMON_START(so, inp, 0);
570 * Must disallow TCP ``connections'' to multicast addresses.
572 sin6p = (struct sockaddr_in6 *)nam;
573 if (sin6p->sin6_family == AF_INET6
574 && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) {
575 error = EAFNOSUPPORT;
579 if (!prison_remote_ip(td, nam)) {
580 error = EAFNOSUPPORT; /* IPv4 only jail */
584 /* Reject v4-mapped address */
585 if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
586 error = EADDRNOTAVAIL;
590 inp->inp_inc.inc_isipv6 = 1;
592 /* msg is invalid now */
595 if (msg->connect.nm_m) {
596 m_freem(msg->connect.nm_m);
597 msg->connect.nm_m = NULL;
599 lwkt_replymsg(&msg->lmsg, error);
605 * Initiate disconnect from peer.
606 * If connection never passed embryonic stage, just drop;
607 * else if don't need to let data drain, then can just drop anyways,
608 * else have to begin TCP shutdown process: mark socket disconnecting,
609 * drain unread data, state switch to reflect user close, and
610 * send segment (e.g. FIN) to peer. Socket will be really disconnected
611 * when peer sends FIN and acks ours.
613 * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.
616 tcp_usr_disconnect(netmsg_t msg)
618 struct socket *so = msg->disconnect.base.nm_so;
623 COMMON_START(so, inp, 1);
624 tp = tcp_disconnect(tp);
625 COMMON_END(PRU_DISCONNECT);
629 * Accept a connection. Essentially all the work is
630 * done at higher levels; just return the address
631 * of the peer, storing through addr.
634 tcp_usr_accept(netmsg_t msg)
636 struct socket *so = msg->accept.base.nm_so;
637 struct sockaddr **nam = msg->accept.nm_nam;
640 struct tcpcb *tp = NULL;
644 if (so->so_state & SS_ISDISCONNECTED) {
645 error = ECONNABORTED;
655 in_setpeeraddr(so, nam);
656 COMMON_END(PRU_ACCEPT);
661 tcp6_usr_accept(netmsg_t msg)
663 struct socket *so = msg->accept.base.nm_so;
664 struct sockaddr **nam = msg->accept.nm_nam;
667 struct tcpcb *tp = NULL;
672 if (so->so_state & SS_ISDISCONNECTED) {
673 error = ECONNABORTED;
682 in6_setpeeraddr(so, nam);
683 COMMON_END(PRU_ACCEPT);
688 * Mark the connection as being incapable of further output.
691 tcp_usr_shutdown(netmsg_t msg)
693 struct socket *so = msg->shutdown.base.nm_so;
698 COMMON_START(so, inp, 0);
700 tp = tcp_usrclosed(tp);
702 error = tcp_output(tp);
703 COMMON_END(PRU_SHUTDOWN);
707 * After a receive, possibly send window update to peer.
710 tcp_usr_rcvd(netmsg_t msg)
712 struct socket *so = msg->rcvd.base.nm_so;
713 int error = 0, noreply = 0;
717 COMMON_START(so, inp, 0);
719 if (msg->rcvd.nm_pru_flags & PRUR_ASYNC) {
721 so_async_rcvd_reply(so);
725 COMMON_END1(PRU_RCVD, noreply);
729 * Do a send by putting data in output queue and updating urgent
730 * marker if URG set. Possibly send more data. Unlike the other
731 * pru_*() routines, the mbuf chains are our responsibility. We
732 * must either enqueue them or free them. The other pru_* routines
733 * generally are caller-frees.
736 tcp_usr_send(netmsg_t msg)
738 struct socket *so = msg->send.base.nm_so;
739 int flags = msg->send.nm_flags;
740 struct mbuf *m = msg->send.nm_m;
746 KKASSERT(msg->send.nm_control == NULL);
747 KKASSERT(msg->send.nm_addr == NULL);
748 KKASSERT((flags & PRUS_FREEADDR) == 0);
754 * OOPS! we lost a race, the TCP session got reset after
755 * we checked SS_CANTSENDMORE, eg: while doing uiomove or a
756 * network interrupt in the non-critical section of sosend().
759 error = ECONNRESET; /* XXX EPIPE? */
769 * This is no longer necessary, since:
770 * - sosendtcp() has already checked it for us
771 * - It does not work with asynchronized send
775 * Don't let too much OOB data build up
777 if (flags & PRUS_OOB) {
778 if (ssb_space(&so->so_snd) < -512) {
787 * Pump the data into the socket.
790 ssb_appendstream(&so->so_snd, m);
793 if (flags & PRUS_OOB) {
795 * According to RFC961 (Assigned Protocols),
796 * the urgent pointer points to the last octet
797 * of urgent data. We continue, however,
798 * to consider it to indicate the first octet
799 * of data past the urgent section.
800 * Otherwise, snd_up should be one lower.
802 tp->snd_up = tp->snd_una + so->so_snd.ssb_cc;
803 tp->t_flags |= TF_FORCE;
804 error = tcp_output(tp);
805 tp->t_flags &= ~TF_FORCE;
807 if (flags & PRUS_EOF) {
809 * Close the send side of the connection after
813 tp = tcp_usrclosed(tp);
815 if (tp != NULL && !tcp_output_pending(tp)) {
816 if (flags & PRUS_MORETOCOME)
817 tp->t_flags |= TF_MORETOCOME;
818 error = tcp_output_fair(tp);
819 if (flags & PRUS_MORETOCOME)
820 tp->t_flags &= ~TF_MORETOCOME;
823 COMMON_END1((flags & PRUS_OOB) ? PRU_SENDOOB :
824 ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND),
825 (flags & PRUS_NOREPLY));
829 * NOTE: (so) is referenced from soabort*() and netmsg_pru_abort()
830 * will sofree() it when we return.
833 tcp_usr_abort(netmsg_t msg)
835 struct socket *so = msg->abort.base.nm_so;
840 COMMON_START(so, inp, 1);
841 tp = tcp_drop(tp, ECONNABORTED);
842 COMMON_END(PRU_ABORT);
846 * Receive out-of-band data.
849 tcp_usr_rcvoob(netmsg_t msg)
851 struct socket *so = msg->rcvoob.base.nm_so;
852 struct mbuf *m = msg->rcvoob.nm_m;
853 int flags = msg->rcvoob.nm_flags;
858 COMMON_START(so, inp, 0);
859 if ((so->so_oobmark == 0 &&
860 (so->so_state & SS_RCVATMARK) == 0) ||
861 so->so_options & SO_OOBINLINE ||
862 tp->t_oobflags & TCPOOB_HADDATA) {
866 if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
871 *mtod(m, caddr_t) = tp->t_iobc;
872 if ((flags & MSG_PEEK) == 0)
873 tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
874 COMMON_END(PRU_RCVOOB);
878 tcp_usr_savefaddr(struct socket *so, const struct sockaddr *faddr)
880 in_savefaddr(so, faddr);
885 tcp6_usr_savefaddr(struct socket *so, const struct sockaddr *faddr)
887 in6_savefaddr(so, faddr);
892 tcp_usr_preconnect(struct socket *so, const struct sockaddr *nam,
893 struct thread *td __unused)
895 const struct sockaddr_in *sinp;
897 sinp = (const struct sockaddr_in *)nam;
898 if (sinp->sin_family == AF_INET &&
899 IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
906 /* xxx - should be const */
907 struct pr_usrreqs tcp_usrreqs = {
908 .pru_abort = tcp_usr_abort,
909 .pru_accept = tcp_usr_accept,
910 .pru_attach = tcp_usr_attach,
911 .pru_bind = tcp_usr_bind,
912 .pru_connect = tcp_usr_connect,
913 .pru_connect2 = pr_generic_notsupp,
914 .pru_control = in_control_dispatch,
915 .pru_detach = tcp_usr_detach,
916 .pru_disconnect = tcp_usr_disconnect,
917 .pru_listen = tcp_usr_listen,
918 .pru_peeraddr = in_setpeeraddr_dispatch,
919 .pru_rcvd = tcp_usr_rcvd,
920 .pru_rcvoob = tcp_usr_rcvoob,
921 .pru_send = tcp_usr_send,
922 .pru_sense = pru_sense_null,
923 .pru_shutdown = tcp_usr_shutdown,
924 .pru_sockaddr = in_setsockaddr_dispatch,
925 .pru_sosend = sosendtcp,
926 .pru_soreceive = sorecvtcp,
927 .pru_savefaddr = tcp_usr_savefaddr,
928 .pru_preconnect = tcp_usr_preconnect,
929 .pru_preattach = tcp_usr_preattach
933 struct pr_usrreqs tcp6_usrreqs = {
934 .pru_abort = tcp_usr_abort,
935 .pru_accept = tcp6_usr_accept,
936 .pru_attach = tcp_usr_attach,
937 .pru_bind = tcp6_usr_bind,
938 .pru_connect = tcp6_usr_connect,
939 .pru_connect2 = pr_generic_notsupp,
940 .pru_control = in6_control_dispatch,
941 .pru_detach = tcp_usr_detach,
942 .pru_disconnect = tcp_usr_disconnect,
943 .pru_listen = tcp6_usr_listen,
944 .pru_peeraddr = in6_setpeeraddr_dispatch,
945 .pru_rcvd = tcp_usr_rcvd,
946 .pru_rcvoob = tcp_usr_rcvoob,
947 .pru_send = tcp_usr_send,
948 .pru_sense = pru_sense_null,
949 .pru_shutdown = tcp_usr_shutdown,
950 .pru_sockaddr = in6_setsockaddr_dispatch,
951 .pru_sosend = sosendtcp,
952 .pru_soreceive = sorecvtcp,
953 .pru_savefaddr = tcp6_usr_savefaddr
958 tcp_connect_oncpu(struct tcpcb *tp, int flags, struct mbuf *m,
959 struct sockaddr_in *sin, struct sockaddr_in *if_sin)
961 struct inpcb *inp = tp->t_inpcb, *oinp;
962 struct socket *so = inp->inp_socket;
963 struct route *ro = &inp->inp_route;
965 KASSERT(inp->inp_pcbinfo == &tcbinfo[mycpu->gd_cpuid],
966 ("pcbinfo mismatch"));
968 oinp = in_pcblookup_hash(inp->inp_pcbinfo,
969 sin->sin_addr, sin->sin_port,
970 (inp->inp_laddr.s_addr != INADDR_ANY ?
971 inp->inp_laddr : if_sin->sin_addr),
972 inp->inp_lport, 0, NULL);
977 if (inp->inp_laddr.s_addr == INADDR_ANY)
978 inp->inp_laddr = if_sin->sin_addr;
979 inp->inp_faddr = sin->sin_addr;
980 inp->inp_fport = sin->sin_port;
981 in_pcbinsconnhash(inp);
984 * We are now on the inpcb's owner CPU, if the cached route was
985 * freed because the rtentry's owner CPU is not the current CPU
986 * (e.g. in tcp_connect()), then we try to reallocate it here with
987 * the hope that a rtentry may be cloned from a RTF_PRCLONING
990 if (!(inp->inp_socket->so_options & SO_DONTROUTE) && /*XXX*/
992 bzero(&ro->ro_dst, sizeof(struct sockaddr_in));
993 ro->ro_dst.sa_family = AF_INET;
994 ro->ro_dst.sa_len = sizeof(struct sockaddr_in);
995 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr =
1001 * Now that no more errors can occur, change the protocol processing
1002 * port to the current thread (which is the correct thread).
1004 * Create TCP timer message now; we are on the tcpcb's owner
1007 tcp_create_timermsg(tp, &curthread->td_msgport);
1010 * Compute window scaling to request. Use a larger scaling then
1011 * needed for the initial receive buffer in case the receive buffer
1014 if (tp->request_r_scale < TCP_MIN_WINSHIFT)
1015 tp->request_r_scale = TCP_MIN_WINSHIFT;
1016 while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1017 (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.ssb_hiwat
1019 tp->request_r_scale++;
1023 tcpstat.tcps_connattempt++;
1024 tp->t_state = TCPS_SYN_SENT;
1025 tcp_callout_reset(tp, tp->tt_keep, tp->t_keepinit, tcp_timer_keep);
1026 tp->iss = tcp_new_isn(tp);
1027 tcp_sendseqinit(tp);
1029 ssb_appendstream(&so->so_snd, m);
1031 if (flags & PRUS_OOB)
1032 tp->snd_up = tp->snd_una + so->so_snd.ssb_cc;
1036 * Close the send side of the connection after
1037 * the data is sent if flagged.
1039 if ((flags & (PRUS_OOB|PRUS_EOF)) == PRUS_EOF) {
1041 tp = tcp_usrclosed(tp);
1043 return (tcp_output(tp));
1047 * Common subroutine to open a TCP connection to remote host specified
1048 * by struct sockaddr_in in mbuf *nam. Call in_pcbbind to assign a local
1049 * port number if needed. Call in_pcbladdr to do the routing and to choose
1050 * a local host address (interface).
1051 * Initialize connection parameters and enter SYN-SENT state.
1054 tcp_connect(netmsg_t msg)
1056 struct socket *so = msg->connect.base.nm_so;
1057 struct sockaddr *nam = msg->connect.nm_nam;
1058 struct thread *td = msg->connect.nm_td;
1059 struct sockaddr_in *sin = (struct sockaddr_in *)nam;
1060 struct sockaddr_in *if_sin = NULL;
1066 COMMON_START(so, inp, 0);
1069 * Reconnect our pcb if we have to
1071 if (msg->connect.nm_flags & PRUC_RECONNECT) {
1072 msg->connect.nm_flags &= ~PRUC_RECONNECT;
1073 in_pcblink(so->so_pcb, &tcbinfo[mycpu->gd_cpuid]);
1077 * Bind if we have to
1079 if (inp->inp_lport == 0) {
1080 if (tcp_lport_extension) {
1081 KKASSERT(inp->inp_laddr.s_addr == INADDR_ANY);
1083 error = in_pcbladdr(inp, nam, &if_sin, td);
1086 inp->inp_laddr.s_addr = if_sin->sin_addr.s_addr;
1088 error = in_pcbbind_remote(inp, nam, td);
1092 msg->connect.nm_flags |= PRUC_HASLADDR;
1094 error = in_pcbbind(inp, NULL, td);
1100 if ((msg->connect.nm_flags & PRUC_HASLADDR) == 0) {
1102 * Calculate the correct protocol processing thread. The
1103 * connect operation must run there. Set the forwarding
1104 * port before we forward the message or it will get bounced
1107 error = in_pcbladdr(inp, nam, &if_sin, td);
1111 KKASSERT(inp->inp_socket == so);
1113 port = tcp_addrport(sin->sin_addr.s_addr, sin->sin_port,
1114 (inp->inp_laddr.s_addr != INADDR_ANY ?
1115 inp->inp_laddr.s_addr : if_sin->sin_addr.s_addr),
1118 if (port != &curthread->td_msgport) {
1119 lwkt_msg_t lmsg = &msg->connect.base.lmsg;
1122 * in_pcbladdr() may have allocated a route entry for us
1123 * on the current CPU, but we need a route entry on the
1124 * inpcb's owner CPU, so free it here.
1126 in_pcbresetroute(inp);
1129 * We are moving the protocol processing port the socket
1130 * is on, we have to unlink here and re-link on the
1133 in_pcbunlink(so->so_pcb, &tcbinfo[mycpu->gd_cpuid]);
1134 msg->connect.nm_flags |= PRUC_RECONNECT;
1135 msg->connect.base.nm_dispatch = tcp_connect;
1138 * Use message put done receipt to change this socket's
1139 * so_port, i.e. _after_ this message was put onto the
1140 * target netisr's msgport but _before_ the message could
1141 * be pulled from the target netisr's msgport, so that:
1142 * - The upper half (socket code) will not see the new
1143 * msgport before this message reaches the new msgport
1144 * and messages for this socket will be ordered.
1145 * - This message will see the new msgport, when its
1146 * handler is called in the target netisr.
1149 * We MUST use messege put done receipt to change this
1151 * If we changed the so_port in this netisr after the
1152 * lwkt_forwardmsg (so messages for this socket will be
1153 * ordered) and changed the so_port in the target netisr
1154 * at the very beginning of this message's handler, we
1155 * would suffer so_port overwritten race, given this
1156 * message might be forwarded again.
1159 * This mechanism depends on that the netisr's msgport
1160 * is spin msgport (currently it is :).
1162 * If the upper half saw the new msgport before this
1163 * message reached the target netisr's msgport, the
1164 * messages sent from the upper half could reach the new
1165 * msgport before this message, thus there would be
1166 * message reordering. The worst case could be soclose()
1167 * saw the new msgport and the detach message could reach
1168 * the new msgport before this message, i.e. the inpcb
1169 * could have been destroyed when this message was still
1170 * pending on or on its way to the new msgport. Other
1171 * weird cases could also happen, e.g. inpcb->inp_pcbinfo,
1172 * since we have unlinked this inpcb from the current
1175 lwkt_setmsg_receipt(lmsg, tcp_sosetport);
1176 lwkt_forwardmsg(port, lmsg);
1177 /* msg invalid now */
1179 } else if (msg->connect.nm_flags & PRUC_HELDTD) {
1181 * The original thread is no longer needed; release it.
1184 msg->connect.nm_flags &= ~PRUC_HELDTD;
1186 error = tcp_connect_oncpu(tp, msg->connect.nm_sndflags,
1187 msg->connect.nm_m, sin, if_sin);
1188 msg->connect.nm_m = NULL;
1190 if (msg->connect.nm_m) {
1191 m_freem(msg->connect.nm_m);
1192 msg->connect.nm_m = NULL;
1194 if (msg->connect.nm_flags & PRUC_HELDTD)
1196 if (error && (msg->connect.nm_flags & PRUC_ASYNC)) {
1197 so->so_error = error;
1198 soisdisconnected(so);
1200 lwkt_replymsg(&msg->connect.base.lmsg, error);
1201 /* msg invalid now */
1207 tcp6_connect(netmsg_t msg)
1210 struct socket *so = msg->connect.base.nm_so;
1211 struct sockaddr *nam = msg->connect.nm_nam;
1212 struct thread *td = msg->connect.nm_td;
1214 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
1215 struct in6_addr *addr6;
1219 COMMON_START(so, inp, 0);
1222 * Reconnect our pcb if we have to
1224 if (msg->connect.nm_flags & PRUC_RECONNECT) {
1225 msg->connect.nm_flags &= ~PRUC_RECONNECT;
1226 in_pcblink(so->so_pcb, &tcbinfo[mycpu->gd_cpuid]);
1230 * Bind if we have to
1232 if (inp->inp_lport == 0) {
1233 error = in6_pcbbind(inp, NULL, td);
1239 * Cannot simply call in_pcbconnect, because there might be an
1240 * earlier incarnation of this same connection still in
1241 * TIME_WAIT state, creating an ADDRINUSE error.
1243 error = in6_pcbladdr(inp, nam, &addr6, td);
1247 port = tcp6_addrport(); /* XXX hack for now, always cpu0 */
1249 if (port != &curthread->td_msgport) {
1250 lwkt_msg_t lmsg = &msg->connect.base.lmsg;
1253 * in_pcbladdr() may have allocated a route entry for us
1254 * on the current CPU, but we need a route entry on the
1255 * inpcb's owner CPU, so free it here.
1257 in_pcbresetroute(inp);
1259 in_pcbunlink(so->so_pcb, &tcbinfo[mycpu->gd_cpuid]);
1260 msg->connect.nm_flags |= PRUC_RECONNECT;
1261 msg->connect.base.nm_dispatch = tcp6_connect;
1263 /* See the related comment in tcp_connect() */
1264 lwkt_setmsg_receipt(lmsg, tcp_sosetport);
1265 lwkt_forwardmsg(port, lmsg);
1266 /* msg invalid now */
1269 error = tcp6_connect_oncpu(tp, msg->connect.nm_sndflags,
1270 &msg->connect.nm_m, sin6, addr6);
1271 /* nm_m may still be intact */
1273 if (msg->connect.nm_m) {
1274 m_freem(msg->connect.nm_m);
1275 msg->connect.nm_m = NULL;
1277 lwkt_replymsg(&msg->connect.base.lmsg, error);
1278 /* msg invalid now */
1282 tcp6_connect_oncpu(struct tcpcb *tp, int flags, struct mbuf **mp,
1283 struct sockaddr_in6 *sin6, struct in6_addr *addr6)
1285 struct mbuf *m = *mp;
1286 struct inpcb *inp = tp->t_inpcb;
1287 struct socket *so = inp->inp_socket;
1291 * Cannot simply call in_pcbconnect, because there might be an
1292 * earlier incarnation of this same connection still in
1293 * TIME_WAIT state, creating an ADDRINUSE error.
1295 oinp = in6_pcblookup_hash(inp->inp_pcbinfo,
1296 &sin6->sin6_addr, sin6->sin6_port,
1297 (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) ?
1298 addr6 : &inp->in6p_laddr),
1299 inp->inp_lport, 0, NULL);
1301 return (EADDRINUSE);
1303 if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr))
1304 inp->in6p_laddr = *addr6;
1305 inp->in6p_faddr = sin6->sin6_addr;
1306 inp->inp_fport = sin6->sin6_port;
1307 if ((sin6->sin6_flowinfo & IPV6_FLOWINFO_MASK) != 0)
1308 inp->in6p_flowinfo = sin6->sin6_flowinfo;
1309 in_pcbinsconnhash(inp);
1312 * Now that no more errors can occur, change the protocol processing
1313 * port to the current thread (which is the correct thread).
1315 * Create TCP timer message now; we are on the tcpcb's owner
1318 tcp_create_timermsg(tp, &curthread->td_msgport);
1320 /* Compute window scaling to request. */
1321 if (tp->request_r_scale < TCP_MIN_WINSHIFT)
1322 tp->request_r_scale = TCP_MIN_WINSHIFT;
1323 while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1324 (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.ssb_hiwat) {
1325 tp->request_r_scale++;
1329 tcpstat.tcps_connattempt++;
1330 tp->t_state = TCPS_SYN_SENT;
1331 tcp_callout_reset(tp, tp->tt_keep, tp->t_keepinit, tcp_timer_keep);
1332 tp->iss = tcp_new_isn(tp);
1333 tcp_sendseqinit(tp);
1335 ssb_appendstream(&so->so_snd, m);
1337 if (flags & PRUS_OOB)
1338 tp->snd_up = tp->snd_una + so->so_snd.ssb_cc;
1342 * Close the send side of the connection after
1343 * the data is sent if flagged.
1345 if ((flags & (PRUS_OOB|PRUS_EOF)) == PRUS_EOF) {
1347 tp = tcp_usrclosed(tp);
1349 return (tcp_output(tp));
1355 * The new sockopt interface makes it possible for us to block in the
1356 * copyin/out step (if we take a page fault). Taking a page fault while
1357 * in a critical section is probably a Bad Thing. (Since sockets and pcbs
1358 * both now use TSM, there probably isn't any need for this function to
1359 * run in a critical section any more. This needs more examination.)
1362 tcp_ctloutput(netmsg_t msg)
1364 struct socket *so = msg->base.nm_so;
1365 struct sockopt *sopt = msg->ctloutput.nm_sopt;
1366 int error, opt, optval, opthz;
1376 tp = intotcpcb(inp);
1378 /* Get socket's owner cpuid hint */
1379 if (sopt->sopt_level == SOL_SOCKET &&
1380 sopt->sopt_dir == SOPT_GET &&
1381 sopt->sopt_name == SO_CPUHINT) {
1382 if (tp->t_flags & TF_LISTEN) {
1384 * Listen sockets owner cpuid is always 0,
1385 * which does not make sense if SO_REUSEPORT
1388 if (so->so_options & SO_REUSEPORT)
1389 optval = (inp->inp_lgrpindex & ncpus2_mask);
1391 optval = -1; /* no hint */
1395 soopt_from_kbuf(sopt, &optval, sizeof(optval));
1399 if (sopt->sopt_level != IPPROTO_TCP) {
1400 if (sopt->sopt_level == IPPROTO_IP) {
1401 switch (sopt->sopt_name) {
1402 case IP_MULTICAST_IF:
1403 case IP_MULTICAST_VIF:
1404 case IP_MULTICAST_TTL:
1405 case IP_MULTICAST_LOOP:
1406 case IP_ADD_MEMBERSHIP:
1407 case IP_DROP_MEMBERSHIP:
1409 * Multicast does not make sense on
1417 if (INP_CHECK_SOCKAF(so, AF_INET6))
1418 ip6_ctloutput_dispatch(msg);
1422 /* msg invalid now */
1426 switch (sopt->sopt_dir) {
1428 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1432 switch (sopt->sopt_name) {
1435 tp->t_keepidle = tp->t_keepintvl;
1437 tp->t_keepidle = tcp_keepidle;
1438 tcp_timer_keep_activity(tp, 0);
1440 #ifdef TCP_SIGNATURE
1441 case TCP_SIGNATURE_ENABLE:
1442 if (tp->t_state == TCPS_CLOSED) {
1444 * This is the only safe state that this
1445 * option could be changed. Some segments
1446 * could already have been sent in other
1450 tp->t_flags |= TF_SIGNATURE;
1452 tp->t_flags &= ~TF_SIGNATURE;
1457 #endif /* TCP_SIGNATURE */
1460 switch (sopt->sopt_name) {
1468 opt = 0; /* dead code to fool gcc */
1475 tp->t_flags &= ~opt;
1479 if (tcp_disable_nopush)
1482 tp->t_flags |= TF_NOPUSH;
1484 tp->t_flags &= ~TF_NOPUSH;
1485 error = tcp_output(tp);
1491 * Must be between 0 and maxseg. If the requested
1492 * maxseg is too small to satisfy the desired minmss,
1493 * pump it up (silently so sysctl modifications of
1494 * minmss do not create unexpected program failures).
1495 * Handle degenerate cases.
1497 if (optval > 0 && optval <= tp->t_maxseg) {
1498 if (optval + 40 < tcp_minmss) {
1499 optval = tcp_minmss - 40;
1503 tp->t_maxseg = optval;
1510 opthz = ((int64_t)optval * hz) / 1000;
1512 tp->t_keepinit = opthz;
1518 opthz = ((int64_t)optval * hz) / 1000;
1520 tp->t_keepidle = opthz;
1521 tcp_timer_keep_activity(tp, 0);
1528 opthz = ((int64_t)optval * hz) / 1000;
1530 tp->t_keepintvl = opthz;
1531 tp->t_maxidle = tp->t_keepintvl * tp->t_keepcnt;
1539 tp->t_keepcnt = optval;
1540 tp->t_maxidle = tp->t_keepintvl * tp->t_keepcnt;
1547 error = ENOPROTOOPT;
1553 switch (sopt->sopt_name) {
1554 #ifdef TCP_SIGNATURE
1555 case TCP_SIGNATURE_ENABLE:
1556 optval = (tp->t_flags & TF_SIGNATURE) ? 1 : 0;
1558 #endif /* TCP_SIGNATURE */
1560 optval = tp->t_flags & TF_NODELAY;
1563 optval = tp->t_maxseg;
1566 optval = tp->t_flags & TF_NOOPT;
1569 optval = tp->t_flags & TF_NOPUSH;
1572 optval = ((int64_t)tp->t_keepinit * 1000) / hz;
1575 optval = ((int64_t)tp->t_keepidle * 1000) / hz;
1578 optval = ((int64_t)tp->t_keepintvl * 1000) / hz;
1581 optval = tp->t_keepcnt;
1584 error = ENOPROTOOPT;
1588 soopt_from_kbuf(sopt, &optval, sizeof optval);
1592 lwkt_replymsg(&msg->lmsg, error);
1596 * tcp_sendspace and tcp_recvspace are the default send and receive window
1597 * sizes, respectively. These are obsolescent (this information should
1598 * be set by the route).
1600 * Use a default that does not require tcp window scaling to be turned
1601 * on. Individual programs or the administrator can increase the default.
1603 u_long tcp_sendspace = 57344; /* largest multiple of PAGE_SIZE < 64k */
1604 SYSCTL_INT(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace, CTLFLAG_RW,
1605 &tcp_sendspace , 0, "Maximum outgoing TCP datagram size");
1606 u_long tcp_recvspace = 57344; /* largest multiple of PAGE_SIZE < 64k */
1607 SYSCTL_INT(_net_inet_tcp, TCPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
1608 &tcp_recvspace , 0, "Maximum incoming TCP datagram size");
1611 * Attach TCP protocol to socket, allocating internet protocol control
1612 * block, tcp control block, buffer space, and entering CLOSED state.
1615 tcp_attach(struct socket *so, struct pru_attach_info *ai)
1622 boolean_t isipv6 = INP_CHECK_SOCKAF(so, AF_INET6);
1626 error = tcp_usr_preattach(so, 0 /* don't care */, ai);
1630 /* Post attach; do nothing */
1633 cpu = mycpu->gd_cpuid;
1636 * Set the default pcbinfo. This will likely change when we
1639 error = in_pcballoc(so, &tcbinfo[cpu]);
1645 inp->in6p_hops = -1; /* use kernel default */
1647 tp = tcp_newtcpcb(inp);
1650 * Make sure the socket is destroyed by the pcbdetach.
1659 sofree(so); /* from ref above */
1662 tp->t_state = TCPS_CLOSED;
1663 /* Keep a reference for asynchronized pru_rcvd */
1669 * Initiate (or continue) disconnect.
1670 * If embryonic state, just send reset (once).
1671 * If in ``let data drain'' option and linger null, just drop.
1672 * Otherwise (hard), mark socket disconnecting and drop
1673 * current input data; switch states based on user close, and
1674 * send segment to peer (with FIN).
1676 static struct tcpcb *
1677 tcp_disconnect(struct tcpcb *tp)
1679 struct socket *so = tp->t_inpcb->inp_socket;
1681 if (tp->t_state < TCPS_ESTABLISHED) {
1683 } else if ((so->so_options & SO_LINGER) && so->so_linger == 0) {
1684 tp = tcp_drop(tp, 0);
1686 lwkt_gettoken(&so->so_rcv.ssb_token);
1687 soisdisconnecting(so);
1688 sbflush(&so->so_rcv.sb);
1689 tp = tcp_usrclosed(tp);
1692 lwkt_reltoken(&so->so_rcv.ssb_token);
1698 * User issued close, and wish to trail through shutdown states:
1699 * if never received SYN, just forget it. If got a SYN from peer,
1700 * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
1701 * If already got a FIN from peer, then almost done; go to LAST_ACK
1702 * state. In all other cases, have already sent FIN to peer (e.g.
1703 * after PRU_SHUTDOWN), and just have to play tedious game waiting
1704 * for peer to send FIN or not respond to keep-alives, etc.
1705 * We can let the user exit from the close as soon as the FIN is acked.
1707 static struct tcpcb *
1708 tcp_usrclosed(struct tcpcb *tp)
1711 switch (tp->t_state) {
1715 tp->t_state = TCPS_CLOSED;
1720 case TCPS_SYN_RECEIVED:
1721 tp->t_flags |= TF_NEEDFIN;
1724 case TCPS_ESTABLISHED:
1725 tp->t_state = TCPS_FIN_WAIT_1;
1728 case TCPS_CLOSE_WAIT:
1729 tp->t_state = TCPS_LAST_ACK;
1732 if (tp && tp->t_state >= TCPS_FIN_WAIT_2) {
1733 soisdisconnected(tp->t_inpcb->inp_socket);
1734 /* To prevent the connection hanging in FIN_WAIT_2 forever. */
1735 if (tp->t_state == TCPS_FIN_WAIT_2) {
1736 tcp_callout_reset(tp, tp->tt_2msl, tp->t_maxidle,