xref: /src/sys/netinet/tcp_usrreq.c

/*	$NetBSD: tcp_usrreq.c,v 1.166.4.5 2014/05/18 17:46:13 rmind Exp $	*/

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*-
 * Copyright (c) 1997, 1998, 2005, 2006 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Jason R. Thorpe and Kevin M. Lahey of the Numerical Aerospace Simulation
 * Facility, NASA Ames Research Center.
 * This code is derived from software contributed to The NetBSD Foundation
 * by Charles M. Hannum.
 * This code is derived from software contributed to The NetBSD Foundation
 * by Rui Paulo.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Copyright (c) 1982, 1986, 1988, 1993, 1995
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)tcp_usrreq.c	8.5 (Berkeley) 6/21/95
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: tcp_usrreq.c,v 1.166.4.5 2014/05/18 17:46:13 rmind Exp $");

#include "opt_inet.h"
#include "opt_ipsec.h"
#include "opt_tcp_debug.h"
#include "opt_mbuftrace.h"


#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/protosw.h>
#include <sys/errno.h>
#include <sys/stat.h>
#include <sys/proc.h>
#include <sys/domain.h>
#include <sys/sysctl.h>
#include <sys/kauth.h>
#include <sys/uidinfo.h>

#include <net/if.h>
#include <net/route.h>

#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/in_pcb.h>
#include <netinet/ip_var.h>
#include <netinet/in_offload.h>

#ifdef INET6
#ifndef INET
#include <netinet/in.h>
#endif
#include <netinet/ip6.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/ip6_var.h>
#include <netinet6/scope6_var.h>
#endif

#include <netinet/tcp.h>
#include <netinet/tcp_fsm.h>
#include <netinet/tcp_seq.h>
#include <netinet/tcp_timer.h>
#include <netinet/tcp_var.h>
#include <netinet/tcp_private.h>
#include <netinet/tcp_congctl.h>
#include <netinet/tcpip.h>
#include <netinet/tcp_debug.h>
#include <netinet/tcp_vtw.h>

#include "opt_tcp_space.h"

/*
 * TCP protocol interface to socket abstraction.
 */

/*
 * Process a TCP user request for TCP tb.  If this is a send request
 * then m is the mbuf chain of send data.  If this is a timer expiration
 * (called from the software clock routine), then timertype tells which timer.
 */
static int
tcp_usrreq(struct socket *so, int req, struct mbuf *m, struct mbuf *nam,
    struct mbuf *control, struct lwp *l)
{
	inpcb_t *inp;
#ifdef INET6
	struct in6pcb *in6p;
#endif
	struct tcpcb *tp = NULL;
	int s;
	int error = 0;
#ifdef TCP_DEBUG
	int ostate = 0;
#endif
	int family;	/* family of the socket */

	KASSERT(req != PRU_ATTACH);
	KASSERT(req != PRU_DETACH);

	family = so->so_proto->pr_domain->dom_family;

	if (req == PRU_CONTROL) {
		switch (family) {
#ifdef INET
		case PF_INET:
			return (in_control(so, (long)m, (void *)nam,
			    (struct ifnet *)control, l));
#endif
#ifdef INET6
		case PF_INET6:
			return (in6_control(so, (long)m, (void *)nam,
			    (struct ifnet *)control, l));
#endif
		default:
			return EAFNOSUPPORT;
		}
	}

	s = splsoftnet();

	if (req == PRU_PURGEIF) {
		mutex_enter(softnet_lock);
		switch (family) {
#ifdef INET
		case PF_INET:
			inpcb_purgeif0(tcbtable, (struct ifnet *)control);
			in_purgeif((struct ifnet *)control);
			inpcb_purgeif(tcbtable, (struct ifnet *)control);
			break;
#endif
#ifdef INET6
		case PF_INET6:
			in6_pcbpurgeif0(tcbtable, (struct ifnet *)control);
			in6_purgeif((struct ifnet *)control);
			in6_pcbpurgeif(tcbtable, (struct ifnet *)control);
			break;
#endif
		default:
			mutex_exit(softnet_lock);
			splx(s);
			return (EAFNOSUPPORT);
		}
		mutex_exit(softnet_lock);
		splx(s);
		return (0);
	}

	KASSERT(solocked(so));

	switch (family) {
#ifdef INET
	case PF_INET:
		inp = sotoinpcb(so);
#ifdef INET6
		in6p = NULL;
#endif
		break;
#endif
#ifdef INET6
	case PF_INET6:
		inp = NULL;
		in6p = sotoin6pcb(so);
		break;
#endif
	default:
		splx(s);
		return EAFNOSUPPORT;
	}

#ifdef INET6
	KASSERT((inp != NULL) ^ (in6p != NULL));
#endif
	KASSERT(!control || (req == PRU_SEND || req == PRU_SENDOOB));

	/*
	 * When a TCP is attached to a socket, then there will be
	 * a (struct inpcb) pointed at by the socket, and this
	 * structure will point at a subsidary (struct tcpcb).
	 */
	if ((inp == NULL
#ifdef INET6
	    && in6p == NULL
#endif
	    ) && req != PRU_SENSE)
	{
		error = EINVAL;
		goto release;
	}
#ifdef INET
	if (inp) {
		tp = intotcpcb(inp);
		/* WHAT IF TP IS 0? */
#ifdef KPROF
		tcp_acounts[tp->t_state][req]++;
#endif
#ifdef TCP_DEBUG
		ostate = tp->t_state;
#endif
	}
#endif
#ifdef INET6
	if (in6p) {
		tp = in6totcpcb(in6p);
		/* WHAT IF TP IS 0? */
#ifdef KPROF
		tcp_acounts[tp->t_state][req]++;
#endif
#ifdef TCP_DEBUG
		ostate = tp->t_state;
#endif
	}
#endif

	switch (req) {
	/*
	 * Give the socket an address.
	 */
	case PRU_BIND:
		switch (family) {
#ifdef INET
		case PF_INET:
			error = inpcb_bind(inp, nam, l);
			break;
#endif
#ifdef INET6
		case PF_INET6:
			error = in6_pcbbind(in6p, nam, l);
			if (!error) {
				/* mapped addr case */
				if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr))
					tp->t_family = AF_INET;
				else
					tp->t_family = AF_INET6;
			}
			break;
#endif
		}
		break;

	/*
	 * Prepare to accept connections.
	 */
	case PRU_LISTEN:
#ifdef INET
		if (inp) {
			in_port_t lport;

			inpcb_get_ports(inp, &lport, NULL);
			if (lport == 0) {
				error = inpcb_bind(inp, NULL, l);
				if (error)
					break;
			}
		}
#endif
#ifdef INET6
		if (in6p && in6p->in6p_lport == 0) {
			error = in6_pcbbind(in6p, NULL, l);
			if (error)
				break;
		}
#endif
		tp->t_state = TCPS_LISTEN;
		break;

	/*
	 * Initiate connection to peer.
	 * Create a template for use in transmissions on this connection.
	 * Enter SYN_SENT state, and mark socket as connecting.
	 * Start keep-alive timer, and seed output sequence space.
	 * Send initial segment on connection.
	 */
	case PRU_CONNECT:
#ifdef INET
		if (inp) {
			in_port_t lport;

			inpcb_get_ports(inp, &lport, NULL);
			if (lport == 0) {
				error = inpcb_bind(inp, NULL, l);
				if (error)
					break;
			}
			error = inpcb_connect(inp, nam, l);
		}
#endif
#ifdef INET6
		if (in6p) {
			if (in6p->in6p_lport == 0) {
				error = in6_pcbbind(in6p, NULL, l);
				if (error)
					break;
			}
			error = in6_pcbconnect(in6p, nam, l);
			if (!error) {
				/* mapped addr case */
				if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr))
					tp->t_family = AF_INET;
				else
					tp->t_family = AF_INET6;
			}
		}
#endif
		if (error)
			break;
		tp->t_template = tcp_template(tp);
		if (tp->t_template == 0) {
#ifdef INET
			if (inp)
				inpcb_disconnect(inp);
#endif
#ifdef INET6
			if (in6p)
				in6_pcbdisconnect(in6p);
#endif
			error = ENOBUFS;
			break;
		}
		/*
		 * Compute window scaling to request.
		 * XXX: This should be moved to tcp_output().
		 */
		while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
		    (TCP_MAXWIN << tp->request_r_scale) < sb_max)
			tp->request_r_scale++;
		soisconnecting(so);
		TCP_STATINC(TCP_STAT_CONNATTEMPT);
		tp->t_state = TCPS_SYN_SENT;
		TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepinit);
		tp->iss = tcp_new_iss(tp, 0);
		tcp_sendseqinit(tp);
		error = tcp_output(tp);
		break;

	/*
	 * Create a TCP connection between two sockets.
	 */
	case PRU_CONNECT2:
		error = EOPNOTSUPP;
		break;

	/*
	 * Initiate disconnect from peer.
	 * If connection never passed embryonic stage, just drop;
	 * else if don't need to let data drain, then can just drop anyways,
	 * else have to begin TCP shutdown process: mark socket disconnecting,
	 * drain unread data, state switch to reflect user close, and
	 * send segment (e.g. FIN) to peer.  Socket will be really disconnected
	 * when peer sends FIN and acks ours.
	 *
	 * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.
	 */
	case PRU_DISCONNECT:
		tp = tcp_disconnect(tp);
		break;

	/*
	 * Accept a connection.  Essentially all the work is
	 * done at higher levels; just return the address
	 * of the peer, storing through addr.
	 */
	case PRU_ACCEPT:
#ifdef INET
		if (inp)
			inpcb_fetch_peeraddr(inp, nam);
#endif
#ifdef INET6
		if (in6p)
			in6_setpeeraddr(in6p, nam);
#endif
		break;

	/*
	 * Mark the connection as being incapable of further output.
	 */
	case PRU_SHUTDOWN:
		socantsendmore(so);
		tp = tcp_usrclosed(tp);
		if (tp)
			error = tcp_output(tp);
		break;

	/*
	 * After a receive, possibly send window update to peer.
	 */
	case PRU_RCVD:
		/*
		 * soreceive() calls this function when a user receives
		 * ancillary data on a listening socket. We don't call
		 * tcp_output in such a case, since there is no header
		 * template for a listening socket and hence the kernel
		 * will panic.
		 */
		if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) != 0)
			(void) tcp_output(tp);
		break;

	/*
	 * Do a send by putting data in output queue and updating urgent
	 * marker if URG set.  Possibly send more data.
	 */
	case PRU_SEND:
		if (control && control->m_len) {
			m_freem(control);
			m_freem(m);
			error = EINVAL;
			break;
		}
		sbappendstream(&so->so_snd, m);
		error = tcp_output(tp);
		break;

	/*
	 * Abort the TCP.
	 */
	case PRU_ABORT:
		tp = tcp_drop(tp, ECONNABORTED);
		break;

	case PRU_SENSE:
		/*
		 * stat: don't bother with a blocksize.
		 */
		splx(s);
		return (0);

	case PRU_RCVOOB:
		if (control && control->m_len) {
			m_freem(control);
			m_freem(m);
			error = EINVAL;
			break;
		}
		if ((so->so_oobmark == 0 &&
		    (so->so_state & SS_RCVATMARK) == 0) ||
		    so->so_options & SO_OOBINLINE ||
		    tp->t_oobflags & TCPOOB_HADDATA) {
			error = EINVAL;
			break;
		}
		if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
			error = EWOULDBLOCK;
			break;
		}
		m->m_len = 1;
		*mtod(m, char *) = tp->t_iobc;
		if (((long)nam & MSG_PEEK) == 0)
			tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
		break;

	case PRU_SENDOOB:
		if (sbspace(&so->so_snd) < -512) {
			m_freem(m);
			error = ENOBUFS;
			break;
		}
		/*
		 * According to RFC961 (Assigned Protocols),
		 * the urgent pointer points to the last octet
		 * of urgent data.  We continue, however,
		 * to consider it to indicate the first octet
		 * of data past the urgent section.
		 * Otherwise, snd_up should be one lower.
		 */
		sbappendstream(&so->so_snd, m);
		tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
		tp->t_force = 1;
		error = tcp_output(tp);
		tp->t_force = 0;
		break;

	case PRU_SOCKADDR:
#ifdef INET
		if (inp)
			inpcb_fetch_sockaddr(inp, nam);
#endif
#ifdef INET6
		if (in6p)
			in6_setsockaddr(in6p, nam);
#endif
		break;

	case PRU_PEERADDR:
#ifdef INET
		if (inp)
			inpcb_fetch_peeraddr(inp, nam);
#endif
#ifdef INET6
		if (in6p)
			in6_setpeeraddr(in6p, nam);
#endif
		break;

	default:
		panic("tcp_usrreq");
	}
#ifdef TCP_DEBUG
	if (tp && (so->so_options & SO_DEBUG))
		tcp_trace(TA_USER, ostate, tp, NULL, req);
#endif

release:
	splx(s);
	return (error);
}

static void
change_keepalive(struct socket *so, struct tcpcb *tp)
{
	tp->t_maxidle = tp->t_keepcnt * tp->t_keepintvl;
	TCP_TIMER_DISARM(tp, TCPT_KEEP);
	TCP_TIMER_DISARM(tp, TCPT_2MSL);

	if (tp->t_state == TCPS_SYN_RECEIVED ||
	    tp->t_state == TCPS_SYN_SENT) {
		TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepinit);
	} else if (so->so_options & SO_KEEPALIVE &&
	    tp->t_state <= TCPS_CLOSE_WAIT) {
		TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepintvl);
	} else {
		TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepidle);
	}

	if ((tp->t_state == TCPS_FIN_WAIT_2) && (tp->t_maxidle > 0))
		TCP_TIMER_ARM(tp, TCPT_2MSL, tp->t_maxidle);
}


int
tcp_ctloutput(int op, struct socket *so, struct sockopt *sopt)
{
	int error = 0, s;
	inpcb_t *inp;
#ifdef INET6
	struct in6pcb *in6p;
#endif
	struct tcpcb *tp;
	u_int ui;
	int family;	/* family of the socket */
	int level, optname, optval;

	level = sopt->sopt_level;
	optname = sopt->sopt_name;

	family = so->so_proto->pr_domain->dom_family;

	s = splsoftnet();
	switch (family) {
#ifdef INET
	case PF_INET:
		inp = sotoinpcb(so);
#ifdef INET6
		in6p = NULL;
#endif
		break;
#endif
#ifdef INET6
	case PF_INET6:
		inp = NULL;
		in6p = sotoin6pcb(so);
		break;
#endif
	default:
		splx(s);
		panic("%s: af %d", __func__, family);
	}
#ifndef INET6
	if (inp == NULL)
#else
	if (inp == NULL && in6p == NULL)
#endif
	{
		splx(s);
		return (ECONNRESET);
	}
	if (level != IPPROTO_TCP) {
		switch (family) {
#ifdef INET
		case PF_INET:
			error = ip_ctloutput(op, so, sopt);
			break;
#endif
#ifdef INET6
		case PF_INET6:
			error = ip6_ctloutput(op, so, sopt);
			break;
#endif
		}
		splx(s);
		return (error);
	}
	if (inp)
		tp = intotcpcb(inp);
#ifdef INET6
	else if (in6p)
		tp = in6totcpcb(in6p);
#endif
	else
		tp = NULL;

	switch (op) {
	case PRCO_SETOPT:
		switch (optname) {
#ifdef TCP_SIGNATURE
		case TCP_MD5SIG:
			error = sockopt_getint(sopt, &optval);
			if (error)
				break;
			if (optval > 0)
				tp->t_flags |= TF_SIGNATURE;
			else
				tp->t_flags &= ~TF_SIGNATURE;
			break;
#endif /* TCP_SIGNATURE */

		case TCP_NODELAY:
			error = sockopt_getint(sopt, &optval);
			if (error)
				break;
			if (optval)
				tp->t_flags |= TF_NODELAY;
			else
				tp->t_flags &= ~TF_NODELAY;
			break;

		case TCP_MAXSEG:
			error = sockopt_getint(sopt, &optval);
			if (error)
				break;
			if (optval > 0 && optval <= tp->t_peermss)
				tp->t_peermss = optval; /* limit on send size */
			else
				error = EINVAL;
			break;
#ifdef notyet
		case TCP_CONGCTL:
			/* XXX string overflow XXX */
			error = tcp_congctl_select(tp, sopt->sopt_data);
			break;
#endif

		case TCP_KEEPIDLE:
			error = sockopt_get(sopt, &ui, sizeof(ui));
			if (error)
				break;
			if (ui > 0) {
				tp->t_keepidle = ui;
				change_keepalive(so, tp);
			} else
				error = EINVAL;
			break;

		case TCP_KEEPINTVL:
			error = sockopt_get(sopt, &ui, sizeof(ui));
			if (error)
				break;
			if (ui > 0) {
				tp->t_keepintvl = ui;
				change_keepalive(so, tp);
			} else
				error = EINVAL;
			break;

		case TCP_KEEPCNT:
			error = sockopt_get(sopt, &ui, sizeof(ui));
			if (error)
				break;
			if (ui > 0) {
				tp->t_keepcnt = ui;
				change_keepalive(so, tp);
			} else
				error = EINVAL;
			break;

		case TCP_KEEPINIT:
			error = sockopt_get(sopt, &ui, sizeof(ui));
			if (error)
				break;
			if (ui > 0) {
				tp->t_keepinit = ui;
				change_keepalive(so, tp);
			} else
				error = EINVAL;
			break;

		default:
			error = ENOPROTOOPT;
			break;
		}
		break;

	case PRCO_GETOPT:
		switch (optname) {
#ifdef TCP_SIGNATURE
		case TCP_MD5SIG:
			optval = (tp->t_flags & TF_SIGNATURE) ? 1 : 0;
			error = sockopt_set(sopt, &optval, sizeof(optval));
			break;
#endif
		case TCP_NODELAY:
			optval = tp->t_flags & TF_NODELAY;
			error = sockopt_set(sopt, &optval, sizeof(optval));
			break;
		case TCP_MAXSEG:
			optval = tp->t_peermss;
			error = sockopt_set(sopt, &optval, sizeof(optval));
			break;
#ifdef notyet
		case TCP_CONGCTL:
			break;
#endif
		default:
			error = ENOPROTOOPT;
			break;
		}
		break;
	}
	splx(s);
	return (error);
}

#ifndef TCP_SENDSPACE
#define	TCP_SENDSPACE	1024*32
#endif
int	tcp_sendspace = TCP_SENDSPACE;
#ifndef TCP_RECVSPACE
#define	TCP_RECVSPACE	1024*32
#endif
int	tcp_recvspace = TCP_RECVSPACE;

/*
 * tcp_attach: attach TCP protocol to socket, allocating internet protocol
 * control block, TCP control block, buffer space and entering LISTEN state
 * if to accept connections.
 */
static int
tcp_attach(struct socket *so, int proto)
{
	inpcb_t *inp;
	struct tcpcb *tp;
#ifdef INET6
	struct in6pcb *in6p;
#endif
	int s, error, family;

	s = splsoftnet();
	sosetlock(so);
	solock(so);

	family = so->so_proto->pr_domain->dom_family;
	switch (family) {
#ifdef INET
	case PF_INET:
		inp = sotoinpcb(so);
#ifdef INET6
		in6p = NULL;
#endif
		break;
#endif
#ifdef INET6
	case PF_INET6:
		inp = NULL;
		in6p = sotoin6pcb(so);
		break;
#endif
	default:
		error = EAFNOSUPPORT;
		goto out;
	}

	KASSERT(inp == NULL);
#ifdef INET6
	KASSERT(in6p == NULL);
#endif

#ifdef MBUFTRACE
	so->so_mowner = &tcp_sock_mowner;
	so->so_rcv.sb_mowner = &tcp_sock_rx_mowner;
	so->so_snd.sb_mowner = &tcp_sock_tx_mowner;
#endif
	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
		error = soreserve(so, tcp_sendspace, tcp_recvspace);
		if (error) {
			goto out;
		}
	}

	so->so_rcv.sb_flags |= SB_AUTOSIZE;
	so->so_snd.sb_flags |= SB_AUTOSIZE;

	tp = NULL;
	switch (family) {
#ifdef INET
	case PF_INET:
		error = inpcb_create(so, tcbtable);
		if ((inp = sotoinpcb(so)) != NULL) {
			tp = tcp_newtcpcb(family, (void *)inp);
		}
#ifdef INET6
		in6p = NULL;
#endif
		break;
#endif
#ifdef INET6
	case PF_INET6:
		error = in6_pcballoc(so, tcbtable);
		if ((in6p = sotoin6pcb(so)) != NULL) {
			tp = tcp_newtcpcb(family, (void *)in6p);
		}
		inp = NULL;
		break;
#endif
	default:
		error = EAFNOSUPPORT;
	}

	if (error) {
		goto out;
	}

	if (tp == NULL) {
		int nofd = so->so_state & SS_NOFDREF;	/* XXX */

		so->so_state &= ~SS_NOFDREF;	/* don't free the socket yet */
#ifdef INET
		if (inp)
			inpcb_destroy(inp);
#endif
#ifdef INET6
		if (in6p)
			in6_pcbdetach(in6p);
#endif
		so->so_state |= nofd;
		error = ENOBUFS;
		goto out;
	}
	tp->t_state = TCPS_CLOSED;

	if ((so->so_options & SO_LINGER) && so->so_linger == 0)
		so->so_linger = TCP_LINGERTIME;
	tp = sototcpcb(so);
out:
	sounlock(so);
	splx(s);
	return error;
}

static void
tcp_detach(struct socket *so)
{
	inpcb_t *inp;
#ifdef INET6
	struct in6pcb *in6p;
#endif
	struct tcpcb *tp = NULL;
	int s, family;

	KASSERT(solocked(so));

	s = splsoftnet();
	family = so->so_proto->pr_domain->dom_family;
	switch (family) {
#ifdef INET
	case PF_INET:
		inp = sotoinpcb(so);
		tp = intotcpcb(inp);
		break;
#endif
#ifdef INET6
	case PF_INET6:
		in6p = sotoin6pcb(so);
		tp = in6totcpcb(in6p);
		break;
#endif
	default:
		splx(s);
		return;
	}
	KASSERT(tp != NULL);
	(void)tcp_disconnect(tp);
	splx(s);
}

/*
 * Initiate (or continue) disconnect.
 * If embryonic state, just send reset (once).
 * If in ``let data drain'' option and linger null, just drop.
 * Otherwise (hard), mark socket disconnecting and drop
 * current input data; switch states based on user close, and
 * send segment to peer (with FIN).
 */
struct tcpcb *
tcp_disconnect(struct tcpcb *tp)
{
	struct socket *so;

	if (tp->t_inpcb)
		so = inpcb_get_socket(tp->t_inpcb);
#ifdef INET6
	else if (tp->t_in6pcb)
		so = tp->t_in6pcb->in6p_socket;
#endif
	else
		so = NULL;

	KASSERT(so != NULL);

	if (TCPS_HAVEESTABLISHED(tp->t_state) == 0)
		tp = tcp_close(tp);
	else if ((so->so_options & SO_LINGER) && so->so_linger == 0)
		tp = tcp_drop(tp, 0);
	else {
		soisdisconnecting(so);
		sbflush(&so->so_rcv);
		tp = tcp_usrclosed(tp);
		if (tp)
			(void) tcp_output(tp);
	}
	return (tp);
}

/*
 * User issued close, and wish to trail through shutdown states:
 * if never received SYN, just forget it.  If got a SYN from peer,
 * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
 * If already got a FIN from peer, then almost done; go to LAST_ACK
 * state.  In all other cases, have already sent FIN to peer (e.g.
 * after PRU_SHUTDOWN), and just have to play tedious game waiting
 * for peer to send FIN or not respond to keep-alives, etc.
 * We can let the user exit from the close as soon as the FIN is acked.
 */
struct tcpcb *
tcp_usrclosed(struct tcpcb *tp)
{

	switch (tp->t_state) {

	case TCPS_CLOSED:
	case TCPS_LISTEN:
	case TCPS_SYN_SENT:
		tp->t_state = TCPS_CLOSED;
		tp = tcp_close(tp);
		break;

	case TCPS_SYN_RECEIVED:
	case TCPS_ESTABLISHED:
		tp->t_state = TCPS_FIN_WAIT_1;
		break;

	case TCPS_CLOSE_WAIT:
		tp->t_state = TCPS_LAST_ACK;
		break;
	}
	if (tp && tp->t_state >= TCPS_FIN_WAIT_2) {
		struct socket *so;
		if (tp->t_inpcb)
			so = inpcb_get_socket(tp->t_inpcb);
#ifdef INET6
		else if (tp->t_in6pcb)
			so = tp->t_in6pcb->in6p_socket;
#endif
		else
			so = NULL;
		if (so)
			soisdisconnected(so);
		/*
		 * If we are in FIN_WAIT_2, we arrived here because the
		 * application did a shutdown of the send side.  Like the
		 * case of a transition from FIN_WAIT_1 to FIN_WAIT_2 after
		 * a full close, we start a timer to make sure sockets are
		 * not left in FIN_WAIT_2 forever.
		 */
		if ((tp->t_state == TCPS_FIN_WAIT_2) && (tp->t_maxidle > 0))
			TCP_TIMER_ARM(tp, TCPT_2MSL, tp->t_maxidle);
		else if (tp->t_state == TCPS_TIME_WAIT
			 && ((tp->t_inpcb
			      && (tcp4_vtw_enable & 1)
			      && vtw_add(AF_INET, tp))
			     ||
			     (tp->t_in6pcb
			      && (tcp6_vtw_enable & 1)
			      && vtw_add(AF_INET6, tp)))) {
			tp = 0;
		}
	}
	return (tp);
}

/*
 * sysctl helper routine for net.inet.ip.mssdflt.  it can't be less
 * than 32.
 */
static int
sysctl_net_inet_tcp_mssdflt(SYSCTLFN_ARGS)
{
	int error, mssdflt;
	struct sysctlnode node;

	mssdflt = tcp_mssdflt;
	node = *rnode;
	node.sysctl_data = &mssdflt;
	error = sysctl_lookup(SYSCTLFN_CALL(&node));
	if (error || newp == NULL)
		return (error);

	if (mssdflt < 32)
		return (EINVAL);
	tcp_mssdflt = mssdflt;

	mutex_enter(softnet_lock);
	tcp_tcpcb_template();
	mutex_exit(softnet_lock);

	return (0);
}

/*
 * sysctl helper for TCP CB template update
 */
static int
sysctl_update_tcpcb_template(SYSCTLFN_ARGS)
{
	int t, error;
	struct sysctlnode node;

	/* follow procedures in sysctl(9) manpage */
	t = *(int *)rnode->sysctl_data;
	node = *rnode;
	node.sysctl_data = &t;
	error = sysctl_lookup(SYSCTLFN_CALL(&node));
	if (error || newp == NULL)
		return error;

	if (t < 0)
		return EINVAL;

	*(int *)rnode->sysctl_data = t;

	mutex_enter(softnet_lock);
	tcp_tcpcb_template();
	mutex_exit(softnet_lock);

	return 0;
}

/*
 * sysctl helper routine for setting port related values under
 * net.inet.ip and net.inet6.ip6.  does basic range checking and does
 * additional checks for each type.  this code has placed in
 * tcp_input.c since INET and INET6 both use the same tcp code.
 *
 * this helper is not static so that both inet and inet6 can use it.
 */
int
sysctl_net_inet_ip_ports(SYSCTLFN_ARGS)
{
	int error, tmp;
	int apmin, apmax;
#ifndef IPNOPRIVPORTS
	int lpmin, lpmax;
#endif /* IPNOPRIVPORTS */
	struct sysctlnode node;

	if (namelen != 0)
		return (EINVAL);

	switch (name[-3]) {
#ifdef INET
	    case PF_INET:
		apmin = anonportmin;
		apmax = anonportmax;
#ifndef IPNOPRIVPORTS
		lpmin = lowportmin;
		lpmax = lowportmax;
#endif /* IPNOPRIVPORTS */
		break;
#endif /* INET */
#ifdef INET6
	    case PF_INET6:
		apmin = ip6_anonportmin;
		apmax = ip6_anonportmax;
#ifndef IPNOPRIVPORTS
		lpmin = ip6_lowportmin;
		lpmax = ip6_lowportmax;
#endif /* IPNOPRIVPORTS */
		break;
#endif /* INET6 */
	    default:
		return (EINVAL);
	}

	/*
	 * insert temporary copy into node, perform lookup on
	 * temporary, then restore pointer
	 */
	node = *rnode;
	tmp = *(int*)rnode->sysctl_data;
	node.sysctl_data = &tmp;
	error = sysctl_lookup(SYSCTLFN_CALL(&node));
	if (error || newp == NULL)
		return (error);

	/*
	 * simple port range check
	 */
	if (tmp < 0 || tmp > 65535)
		return (EINVAL);

	/*
	 * per-node range checks
	 */
	switch (rnode->sysctl_num) {
	case IPCTL_ANONPORTMIN:
	case IPV6CTL_ANONPORTMIN:
		if (tmp >= apmax)
			return (EINVAL);
#ifndef IPNOPRIVPORTS
		if (tmp < IPPORT_RESERVED)
                        return (EINVAL);
#endif /* IPNOPRIVPORTS */
		break;

	case IPCTL_ANONPORTMAX:
	case IPV6CTL_ANONPORTMAX:
                if (apmin >= tmp)
			return (EINVAL);
#ifndef IPNOPRIVPORTS
		if (tmp < IPPORT_RESERVED)
                        return (EINVAL);
#endif /* IPNOPRIVPORTS */
		break;

#ifndef IPNOPRIVPORTS
	case IPCTL_LOWPORTMIN:
	case IPV6CTL_LOWPORTMIN:
		if (tmp >= lpmax ||
		    tmp > IPPORT_RESERVEDMAX ||
		    tmp < IPPORT_RESERVEDMIN)
			return (EINVAL);
		break;

	case IPCTL_LOWPORTMAX:
	case IPV6CTL_LOWPORTMAX:
		if (lpmin >= tmp ||
		    tmp > IPPORT_RESERVEDMAX ||
		    tmp < IPPORT_RESERVEDMIN)
			return (EINVAL);
		break;
#endif /* IPNOPRIVPORTS */

	default:
		return (EINVAL);
	}

	*(int*)rnode->sysctl_data = tmp;

	return (0);
}

static inline int
copyout_uid(struct socket *sockp, void *oldp, size_t *oldlenp)
{
	if (oldp) {
		size_t sz;
		uid_t uid;
		int error;

		if (sockp->so_cred == NULL)
			return EPERM;

		uid = kauth_cred_geteuid(sockp->so_cred);
		sz = MIN(sizeof(uid), *oldlenp);
		if ((error = copyout(&uid, oldp, sz)) != 0)
			return error;
	}
	*oldlenp = sizeof(uid_t);
	return 0;
}

static inline int
inet4_ident_core(struct in_addr raddr, u_int rport,
    struct in_addr laddr, u_int lport,
    void *oldp, size_t *oldlenp,
    struct lwp *l, int dodrop)
{
	inpcb_t *inp;
	struct socket *so;

	inp = inpcb_lookup(tcbtable, raddr, rport, laddr, lport, NULL);
	if (inp == NULL || (so = inpcb_get_socket(inp)) == NULL)
		return ESRCH;

	if (dodrop) {
		struct tcpcb *tp;
		int error;

		if ((tp = intotcpcb(inp)) == NULL ||
		    (so->so_options & SO_ACCEPTCONN) != 0)
			return ESRCH;

		error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_SOCKET,
		    KAUTH_REQ_NETWORK_SOCKET_DROP, so, tp, NULL);
		if (error) {
			return error;
		}

		(void)tcp_drop(tp, ECONNABORTED);
		return 0;
	}

	return copyout_uid(so, oldp, oldlenp);
}

#ifdef INET6
static inline int
inet6_ident_core(struct in6_addr *raddr, u_int rport,
    struct in6_addr *laddr, u_int lport,
    void *oldp, size_t *oldlenp,
    struct lwp *l, int dodrop)
{
	struct in6pcb *in6p;
	struct socket *sockp;

	in6p = in6_pcblookup_connect(tcbtable, raddr, rport, laddr, lport, 0, 0);

	if (in6p == NULL || (sockp = in6p->in6p_socket) == NULL)
		return ESRCH;

	if (dodrop) {
		struct tcpcb *tp;
		int error;

		if (in6p == NULL || (tp = in6totcpcb(in6p)) == NULL ||
		    (in6p->in6p_socket->so_options & SO_ACCEPTCONN) != 0)
			return ESRCH;

		error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_SOCKET,
		    KAUTH_REQ_NETWORK_SOCKET_DROP, in6p->in6p_socket, tp, NULL);
		if (error)
			return (error);

		(void)tcp_drop(tp, ECONNABORTED);
		return 0;
	}
	else
		return copyout_uid(sockp, oldp, oldlenp);
}
#endif

/*
 * sysctl helper routine for the net.inet.tcp.drop and
 * net.inet6.tcp6.drop nodes.
 */
#define sysctl_net_inet_tcp_drop sysctl_net_inet_tcp_ident

/*
 * sysctl helper routine for the net.inet.tcp.ident and
 * net.inet6.tcp6.ident nodes.  contains backwards compat code for the
 * old way of looking up the ident information for ipv4 which involves
 * stuffing the port/addr pairs into the mib lookup.
 */
static int
sysctl_net_inet_tcp_ident(SYSCTLFN_ARGS)
{
#ifdef INET
	struct sockaddr_in *si4[2];
#endif /* INET */
#ifdef INET6
	struct sockaddr_in6 *si6[2];
#endif /* INET6 */
	struct sockaddr_storage sa[2];
	int error, pf, dodrop;

	dodrop = name[-1] == TCPCTL_DROP;
	if (dodrop) {
		if (oldp != NULL || *oldlenp != 0)
			return EINVAL;
		if (newp == NULL)
			return EPERM;
		if (newlen < sizeof(sa))
			return ENOMEM;
	}
	if (namelen != 4 && namelen != 0)
		return EINVAL;
	if (name[-2] != IPPROTO_TCP)
		return EINVAL;
	pf = name[-3];

	/* old style lookup, ipv4 only */
	if (namelen == 4) {
#ifdef INET
		struct in_addr laddr, raddr;
		u_int lport, rport;

		if (pf != PF_INET)
			return EPROTONOSUPPORT;
		raddr.s_addr = (uint32_t)name[0];
		rport = (u_int)name[1];
		laddr.s_addr = (uint32_t)name[2];
		lport = (u_int)name[3];

		mutex_enter(softnet_lock);
		error = inet4_ident_core(raddr, rport, laddr, lport,
		    oldp, oldlenp, l, dodrop);
		mutex_exit(softnet_lock);
		return error;
#else /* INET */
		return EINVAL;
#endif /* INET */
	}

	if (newp == NULL || newlen != sizeof(sa))
		return EINVAL;
	error = copyin(newp, &sa, newlen);
	if (error)
		return error;

	/*
	 * requested families must match
	 */
	if (pf != sa[0].ss_family || sa[0].ss_family != sa[1].ss_family)
		return EINVAL;

	switch (pf) {
#ifdef INET6
	case PF_INET6:
		si6[0] = (struct sockaddr_in6*)&sa[0];
		si6[1] = (struct sockaddr_in6*)&sa[1];
		if (si6[0]->sin6_len != sizeof(*si6[0]) ||
		    si6[1]->sin6_len != sizeof(*si6[1]))
			return EINVAL;

		if (!IN6_IS_ADDR_V4MAPPED(&si6[0]->sin6_addr) &&
		    !IN6_IS_ADDR_V4MAPPED(&si6[1]->sin6_addr)) {
			error = sa6_embedscope(si6[0], ip6_use_defzone);
			if (error)
				return error;
			error = sa6_embedscope(si6[1], ip6_use_defzone);
			if (error)
				return error;

			mutex_enter(softnet_lock);
			error = inet6_ident_core(&si6[0]->sin6_addr,
			    si6[0]->sin6_port, &si6[1]->sin6_addr,
			    si6[1]->sin6_port, oldp, oldlenp, l, dodrop);
			mutex_exit(softnet_lock);
			return error;
		}

		if (IN6_IS_ADDR_V4MAPPED(&si6[0]->sin6_addr) !=
		    IN6_IS_ADDR_V4MAPPED(&si6[1]->sin6_addr))
			return EINVAL;

		in6_sin6_2_sin_in_sock((struct sockaddr *)&sa[0]);
		in6_sin6_2_sin_in_sock((struct sockaddr *)&sa[1]);
		/*FALLTHROUGH*/
#endif /* INET6 */
#ifdef INET
	case PF_INET:
		si4[0] = (struct sockaddr_in*)&sa[0];
		si4[1] = (struct sockaddr_in*)&sa[1];
		if (si4[0]->sin_len != sizeof(*si4[0]) ||
		    si4[0]->sin_len != sizeof(*si4[1]))
			return EINVAL;

		mutex_enter(softnet_lock);
		error = inet4_ident_core(si4[0]->sin_addr, si4[0]->sin_port,
		    si4[1]->sin_addr, si4[1]->sin_port,
		    oldp, oldlenp, l, dodrop);
		mutex_exit(softnet_lock);
		return error;
#endif /* INET */
	default:
		return EPROTONOSUPPORT;
	}
}

static int
sysctl_tcp_congctl(SYSCTLFN_ARGS)
{
	struct sysctlnode node;
	int error;
	char newname[TCPCC_MAXLEN];

	strlcpy(newname, tcp_congctl_global_name, sizeof(newname) - 1);

	node = *rnode;
	node.sysctl_data = newname;
	node.sysctl_size = sizeof(newname);

	error = sysctl_lookup(SYSCTLFN_CALL(&node));

	if (error ||
	    newp == NULL ||
	    strncmp(newname, tcp_congctl_global_name, sizeof(newname)) == 0)
		return error;

	mutex_enter(softnet_lock);
	error = tcp_congctl_select(NULL, newname);
	mutex_exit(softnet_lock);

	return error;
}

static int
sysctl_tcp_init_win(SYSCTLFN_ARGS)
{
	int error;
	u_int iw;
	struct sysctlnode node;

	iw = *(u_int *)rnode->sysctl_data;
	node = *rnode;
	node.sysctl_data = &iw;
	node.sysctl_size = sizeof(iw);
	error = sysctl_lookup(SYSCTLFN_CALL(&node));
	if (error || newp == NULL)
		return error;

	if (iw >= __arraycount(tcp_init_win_max))
		return EINVAL;
	*(u_int *)rnode->sysctl_data = iw;
	return 0;
}

static int
sysctl_tcp_keep(SYSCTLFN_ARGS)
{
	int error;
	u_int tmp;
	struct sysctlnode node;

	node = *rnode;
	tmp = *(u_int *)rnode->sysctl_data;
	node.sysctl_data = &tmp;

	error = sysctl_lookup(SYSCTLFN_CALL(&node));
	if (error || newp == NULL)
		return error;

	mutex_enter(softnet_lock);

	*(u_int *)rnode->sysctl_data = tmp;
	tcp_tcpcb_template();	/* update the template */

	mutex_exit(softnet_lock);
	return 0;
}

static int
sysctl_net_inet_tcp_stats(SYSCTLFN_ARGS)
{

	return (NETSTAT_SYSCTL(tcpstat_percpu, TCP_NSTATS));
}

/*
 * this (second stage) setup routine is a replacement for tcp_sysctl()
 * (which is currently used for ipv4 and ipv6)
 */
static void
sysctl_net_inet_tcp_setup2(struct sysctllog **clog, int pf, const char *pfname,
			   const char *tcpname)
{
	const struct sysctlnode *sack_node;
	const struct sysctlnode *abc_node;
	const struct sysctlnode *ecn_node;
	const struct sysctlnode *congctl_node;
	const struct sysctlnode *mslt_node;
	const struct sysctlnode *vtw_node;
#ifdef TCP_DEBUG
	extern struct tcp_debug tcp_debug[TCP_NDEBUG];
	extern int tcp_debx;
#endif

	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT,
		       CTLTYPE_NODE, pfname, NULL,
		       NULL, 0, NULL, 0,
		       CTL_NET, pf, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT,
		       CTLTYPE_NODE, tcpname,
		       SYSCTL_DESCR("TCP related settings"),
		       NULL, 0, NULL, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_EOL);

	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "rfc1323",
		       SYSCTL_DESCR("Enable RFC1323 TCP extensions"),
		       sysctl_update_tcpcb_template, 0, &tcp_do_rfc1323, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_RFC1323, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "sendspace",
		       SYSCTL_DESCR("Default TCP send buffer size"),
		       NULL, 0, &tcp_sendspace, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_SENDSPACE, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "recvspace",
		       SYSCTL_DESCR("Default TCP receive buffer size"),
		       NULL, 0, &tcp_recvspace, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_RECVSPACE, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "mssdflt",
		       SYSCTL_DESCR("Default maximum segment size"),
		       sysctl_net_inet_tcp_mssdflt, 0, &tcp_mssdflt, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_MSSDFLT, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "minmss",
		       SYSCTL_DESCR("Lower limit for TCP maximum segment size"),
		       NULL, 0, &tcp_minmss, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "msl",
		       SYSCTL_DESCR("Maximum Segment Life"),
		       NULL, 0, &tcp_msl, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_MSL, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "syn_cache_limit",
		       SYSCTL_DESCR("Maximum number of entries in the TCP "
				    "compressed state engine"),
		       NULL, 0, &tcp_syn_cache_limit, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_SYN_CACHE_LIMIT,
		       CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "syn_bucket_limit",
		       SYSCTL_DESCR("Maximum number of entries per hash "
				    "bucket in the TCP compressed state "
				    "engine"),
		       NULL, 0, &tcp_syn_bucket_limit, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_SYN_BUCKET_LIMIT,
		       CTL_EOL);
#if 0 /* obsoleted */
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "syn_cache_interval",
		       SYSCTL_DESCR("TCP compressed state engine's timer interval"),
		       NULL, 0, &tcp_syn_cache_interval, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_SYN_CACHE_INTER,
		       CTL_EOL);
#endif
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "init_win",
		       SYSCTL_DESCR("Initial TCP congestion window"),
		       sysctl_tcp_init_win, 0, &tcp_init_win, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_INIT_WIN, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "mss_ifmtu",
		       SYSCTL_DESCR("Use interface MTU for calculating MSS"),
		       NULL, 0, &tcp_mss_ifmtu, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_MSS_IFMTU, CTL_EOL);
	sysctl_createv(clog, 0, NULL, &sack_node,
		       CTLFLAG_PERMANENT,
		       CTLTYPE_NODE, "sack",
		       SYSCTL_DESCR("RFC2018 Selective ACKnowledgement tunables"),
		       NULL, 0, NULL, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_SACK, CTL_EOL);

	/* Congctl subtree */
	sysctl_createv(clog, 0, NULL, &congctl_node,
		       CTLFLAG_PERMANENT,
		       CTLTYPE_NODE, "congctl",
		       SYSCTL_DESCR("TCP Congestion Control"),
	    	       NULL, 0, NULL, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, &congctl_node, NULL,
		       CTLFLAG_PERMANENT,
		       CTLTYPE_STRING, "available",
		       SYSCTL_DESCR("Available Congestion Control Mechanisms"),
		       NULL, 0, tcp_congctl_avail, 0, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, &congctl_node, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_STRING, "selected",
		       SYSCTL_DESCR("Selected Congestion Control Mechanism"),
		       sysctl_tcp_congctl, 0, NULL, TCPCC_MAXLEN,
		       CTL_CREATE, CTL_EOL);

	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "win_scale",
		       SYSCTL_DESCR("Use RFC1323 window scale options"),
		       sysctl_update_tcpcb_template, 0, &tcp_do_win_scale, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_WSCALE, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "timestamps",
		       SYSCTL_DESCR("Use RFC1323 time stamp options"),
		       sysctl_update_tcpcb_template, 0, &tcp_do_timestamps, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_TSTAMP, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "compat_42",
		       SYSCTL_DESCR("Enable workarounds for 4.2BSD TCP bugs"),
		       NULL, 0, &tcp_compat_42, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_COMPAT_42, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "cwm",
		       SYSCTL_DESCR("Hughes/Touch/Heidemann Congestion Window "
				    "Monitoring"),
		       NULL, 0, &tcp_cwm, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_CWM, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "cwm_burstsize",
		       SYSCTL_DESCR("Congestion Window Monitoring allowed "
				    "burst count in packets"),
		       NULL, 0, &tcp_cwm_burstsize, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_CWM_BURSTSIZE,
		       CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "ack_on_push",
		       SYSCTL_DESCR("Immediately return ACK when PSH is "
				    "received"),
		       NULL, 0, &tcp_ack_on_push, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_ACK_ON_PUSH, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "keepidle",
		       SYSCTL_DESCR("Allowed connection idle ticks before a "
				    "keepalive probe is sent"),
		       sysctl_tcp_keep, 0, &tcp_keepidle, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_KEEPIDLE, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "keepintvl",
		       SYSCTL_DESCR("Ticks before next keepalive probe is sent"),
		       sysctl_tcp_keep, 0, &tcp_keepintvl, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_KEEPINTVL, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "keepcnt",
		       SYSCTL_DESCR("Number of keepalive probes to send"),
		       sysctl_tcp_keep, 0, &tcp_keepcnt, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_KEEPCNT, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_IMMEDIATE,
		       CTLTYPE_INT, "slowhz",
		       SYSCTL_DESCR("Keepalive ticks per second"),
		       NULL, PR_SLOWHZ, NULL, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_SLOWHZ, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "log_refused",
		       SYSCTL_DESCR("Log refused TCP connections"),
		       NULL, 0, &tcp_log_refused, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_LOG_REFUSED, CTL_EOL);
#if 0 /* obsoleted */
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "rstratelimit", NULL,
		       NULL, 0, &tcp_rst_ratelim, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_RSTRATELIMIT, CTL_EOL);
#endif
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "rstppslimit",
		       SYSCTL_DESCR("Maximum number of RST packets to send "
				    "per second"),
		       NULL, 0, &tcp_rst_ppslim, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_RSTPPSLIMIT, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "delack_ticks",
		       SYSCTL_DESCR("Number of ticks to delay sending an ACK"),
		       NULL, 0, &tcp_delack_ticks, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_DELACK_TICKS, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "init_win_local",
		       SYSCTL_DESCR("Initial TCP window size (in segments)"),
		       sysctl_tcp_init_win, 0, &tcp_init_win_local, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_INIT_WIN_LOCAL,
		       CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_STRUCT, "ident",
		       SYSCTL_DESCR("RFC1413 Identification Protocol lookups"),
		       sysctl_net_inet_tcp_ident, 0, NULL, sizeof(uid_t),
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_IDENT, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "do_loopback_cksum",
		       SYSCTL_DESCR("Perform TCP checksum on loopback"),
		       NULL, 0, &tcp_do_loopback_cksum, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_LOOPBACKCKSUM,
		       CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT,
		       CTLTYPE_STRUCT, "pcblist",
		       SYSCTL_DESCR("TCP protocol control block list"),
		       sysctl_inpcblist, 0, tcbtable, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE,
		       CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "keepinit",
		       SYSCTL_DESCR("Ticks before initial tcp connection times out"),
		       sysctl_tcp_keep, 0, &tcp_keepinit, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE, CTL_EOL);

	/* TCP socket buffers auto-sizing nodes */
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "recvbuf_auto",
		       SYSCTL_DESCR("Enable automatic receive "
		           "buffer sizing (experimental)"),
		       NULL, 0, &tcp_do_autorcvbuf, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "recvbuf_inc",
		       SYSCTL_DESCR("Incrementor step size of "
		           "automatic receive buffer"),
		       NULL, 0, &tcp_autorcvbuf_inc, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "recvbuf_max",
		       SYSCTL_DESCR("Max size of automatic receive buffer"),
		       NULL, 0, &tcp_autorcvbuf_max, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE, CTL_EOL);

	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "sendbuf_auto",
		       SYSCTL_DESCR("Enable automatic send "
		           "buffer sizing (experimental)"),
		       NULL, 0, &tcp_do_autosndbuf, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "sendbuf_inc",
		       SYSCTL_DESCR("Incrementor step size of "
		           "automatic send buffer"),
		       NULL, 0, &tcp_autosndbuf_inc, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "sendbuf_max",
		       SYSCTL_DESCR("Max size of automatic send buffer"),
		       NULL, 0, &tcp_autosndbuf_max, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE, CTL_EOL);

	/* ECN subtree */
	sysctl_createv(clog, 0, NULL, &ecn_node,
	    	       CTLFLAG_PERMANENT,
		       CTLTYPE_NODE, "ecn",
	    	       SYSCTL_DESCR("RFC3168 Explicit Congestion Notification"),
	    	       NULL, 0, NULL, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, &ecn_node, NULL,
	    	       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "enable",
		       SYSCTL_DESCR("Enable TCP Explicit Congestion "
			   "Notification"),
	    	       NULL, 0, &tcp_do_ecn, 0, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, &ecn_node, NULL,
	    	       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "maxretries",
		       SYSCTL_DESCR("Number of times to retry ECN setup "
			       "before disabling ECN on the connection"),
	    	       NULL, 0, &tcp_ecn_maxretries, 0, CTL_CREATE, CTL_EOL);

	/* SACK gets it's own little subtree. */
	sysctl_createv(clog, 0, NULL, &sack_node,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "enable",
		       SYSCTL_DESCR("Enable RFC2018 Selective ACKnowledgement"),
		       NULL, 0, &tcp_do_sack, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_SACK, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, NULL, &sack_node,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "maxholes",
		       SYSCTL_DESCR("Maximum number of TCP SACK holes allowed per connection"),
		       NULL, 0, &tcp_sack_tp_maxholes, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_SACK, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, NULL, &sack_node,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "globalmaxholes",
		       SYSCTL_DESCR("Global maximum number of TCP SACK holes"),
		       NULL, 0, &tcp_sack_globalmaxholes, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_SACK, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, NULL, &sack_node,
		       CTLFLAG_PERMANENT,
		       CTLTYPE_INT, "globalholes",
		       SYSCTL_DESCR("Global number of TCP SACK holes"),
		       NULL, 0, &tcp_sack_globalholes, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_SACK, CTL_CREATE, CTL_EOL);

	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT,
		       CTLTYPE_STRUCT, "stats",
		       SYSCTL_DESCR("TCP statistics"),
		       sysctl_net_inet_tcp_stats, 0, NULL, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_STATS,
		       CTL_EOL);
        sysctl_createv(clog, 0, NULL, NULL,
                       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
                       CTLTYPE_INT, "local_by_rtt",
                       SYSCTL_DESCR("Use RTT estimator to decide which hosts "
				    "are local"),
		       NULL, 0, &tcp_rttlocal, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE, CTL_EOL);
#ifdef TCP_DEBUG
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT,
		       CTLTYPE_STRUCT, "debug",
		       SYSCTL_DESCR("TCP sockets debug information"),
		       NULL, 0, &tcp_debug, sizeof(tcp_debug),
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_DEBUG,
		       CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT,
		       CTLTYPE_INT, "debx",
		       SYSCTL_DESCR("Number of TCP debug sockets messages"),
		       NULL, 0, &tcp_debx, sizeof(tcp_debx),
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_DEBX,
		       CTL_EOL);
#endif
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_STRUCT, "drop",
		       SYSCTL_DESCR("TCP drop connection"),
		       sysctl_net_inet_tcp_drop, 0, NULL, 0,
		       CTL_NET, pf, IPPROTO_TCP, TCPCTL_DROP, CTL_EOL);
	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "iss_hash",
		       SYSCTL_DESCR("Enable RFC 1948 ISS by cryptographic "
				    "hash computation"),
		       NULL, 0, &tcp_do_rfc1948, sizeof(tcp_do_rfc1948),
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE,
		       CTL_EOL);

	/* ABC subtree */

	sysctl_createv(clog, 0, NULL, &abc_node,
		       CTLFLAG_PERMANENT, CTLTYPE_NODE, "abc",
		       SYSCTL_DESCR("RFC3465 Appropriate Byte Counting (ABC)"),
		       NULL, 0, NULL, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, &abc_node, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "enable",
		       SYSCTL_DESCR("Enable RFC3465 Appropriate Byte Counting"),
		       NULL, 0, &tcp_do_abc, 0, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, &abc_node, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "aggressive",
		       SYSCTL_DESCR("1: L=2*SMSS 0: L=1*SMSS"),
		       NULL, 0, &tcp_abc_aggressive, 0, CTL_CREATE, CTL_EOL);

	/* MSL tuning subtree */

	sysctl_createv(clog, 0, NULL, &mslt_node,
		       CTLFLAG_PERMANENT, CTLTYPE_NODE, "mslt",
		       SYSCTL_DESCR("MSL Tuning for TIME_WAIT truncation"),
		       NULL, 0, NULL, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, &mslt_node, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "enable",
		       SYSCTL_DESCR("Enable TIME_WAIT truncation"),
		       NULL, 0, &tcp_msl_enable, 0, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, &mslt_node, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "loopback",
		       SYSCTL_DESCR("MSL value to use for loopback connections"),
		       NULL, 0, &tcp_msl_loop, 0, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, &mslt_node, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "local",
		       SYSCTL_DESCR("MSL value to use for local connections"),
		       NULL, 0, &tcp_msl_local, 0, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, &mslt_node, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "remote",
		       SYSCTL_DESCR("MSL value to use for remote connections"),
		       NULL, 0, &tcp_msl_remote, 0, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, &mslt_node, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "remote_threshold",
		       SYSCTL_DESCR("RTT estimate value to promote local to remote"),
		       NULL, 0, &tcp_msl_remote_threshold, 0, CTL_CREATE, CTL_EOL);

	/* vestigial TIME_WAIT tuning subtree */

	sysctl_createv(clog, 0, NULL, &vtw_node,
		       CTLFLAG_PERMANENT, CTLTYPE_NODE, "vtw",
		       SYSCTL_DESCR("Tuning for Vestigial TIME_WAIT"),
		       NULL, 0, NULL, 0,
		       CTL_NET, pf, IPPROTO_TCP, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, &vtw_node, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
		       CTLTYPE_INT, "enable",
		       SYSCTL_DESCR("Enable Vestigial TIME_WAIT"),
		       sysctl_tcp_vtw_enable, 0,
	               (pf == AF_INET) ? &tcp4_vtw_enable : &tcp6_vtw_enable,
		       0, CTL_CREATE, CTL_EOL);
	sysctl_createv(clog, 0, &vtw_node, NULL,
		       CTLFLAG_PERMANENT|CTLFLAG_READONLY,
		       CTLTYPE_INT, "entries",
		       SYSCTL_DESCR("Maximum number of vestigial TIME_WAIT entries"),
		       NULL, 0, &tcp_vtw_entries, 0, CTL_CREATE, CTL_EOL);
}

void
tcp_usrreq_init(void)
{

#ifdef INET
	sysctl_net_inet_tcp_setup2(NULL, PF_INET, "inet", "tcp");
#endif
#ifdef INET6
	sysctl_net_inet_tcp_setup2(NULL, PF_INET6, "inet6", "tcp6");
#endif
}

PR_WRAP_USRREQ(tcp_usrreq)

#define	tcp_usrreq	tcp_usrreq_wrapper

const struct pr_usrreqs tcp_usrreqs = {
	.pr_attach	= tcp_attach,
	.pr_detach	= tcp_detach,
	.pr_generic	= tcp_usrreq,
};