www.pudn.com > vxworks_tcpip_code.rar > rtsock.c


/* rtsock.c - routines for routing sockets */

/* Copyright 1990-1996 Wind River Systems, Inc. */
#include "copyright_wrs.h"

/*
 * Copyright (c) 1988, 1991, 1993
 *	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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. 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.
 *
 *	@(#)rtsock.c	8.6 (Berkeley) 2/11/95
 */

/*
modification history
--------------------
01g,27oct99,pul  routing interface enhancements
01f,26aug98,n_s  added return val check for MALLOC in route_usrreq. spr #22238.
01e,04dec97,vin  moved back m_copyback and m_copydata from uipc_mbuf.c as
		 these are only used in rt_sock. Ifdefed m_copyback and
                 m_copydata in uipc_mbuf.c these need some rework so that
                 they can be tied up efficiently with the new buffering scheme.
01d,01jul97,vin  added rtSockInit, removed route_init from routedomain, it is
		 called from netLibInit. Added route message hooks for
                 scalability.
01c,05dec96,vin  changed malloc(..) to MALLOC(..) to use only network buffers,
		 changed free(..) to FREE(..).
01b,22nov96,vin  added cluster support replaced m_get(..) with mBufClGet(..).
		 m_gethdr(..) with mHdrClGet(..), moved m_copyback(..) to 
		 uipc_mbuf.c
01a,03mar96,vin  created from BSD4.4lite2.
*/

#include "net/systm.h"
#include "net/mbuf.h"
#include "sys/socket.h"
#include "net/socketvar.h"
#include "net/domain.h"
#include "net/protosw.h"
#include "net/unixLib.h"

#include "net/if.h"
#include "net/route.h"
#include "net/raw_cb.h"

#include "routeEnhLib.h"
struct walkarg {
	int	w_op, w_arg, w_given, w_needed, w_tmemsize;
	caddr_t	w_where, w_tmem;
};

static struct	sockaddr route_dst = { 2, PF_ROUTE, };
static struct	sockaddr route_src = { 2, PF_ROUTE, };
static struct	sockproto route_proto = { PF_ROUTE, };

static struct mbuf *
		rt_msg1 (int, struct rt_addrinfo *);
static int	rt_msg2 (int, struct rt_addrinfo *, caddr_t, 
			 struct walkarg *);
static void	rt_xaddrs (caddr_t, caddr_t, struct rt_addrinfo *);

static int	route_usrreq (struct socket *, int, struct mbuf *,
                              struct mbuf *, struct mbuf *);
static void	rt_ifmsg (struct ifnet *);
static void	rt_missmsg (int, struct rt_addrinfo *, int, int);
static void	rt_newaddrmsg (int, struct ifaddr *, int, struct rtentry *);
static int	route_output (struct mbuf *, struct socket *);
static void	rt_setmetrics (u_long, struct rt_metrics *,
                               struct rt_metrics *);

static void	m_copyback (struct mbuf *, int, int, caddr_t);
static void 	m_copydata(struct mbuf *, int, int, caddr_t);

/* Sleazy use of local variables throughout file, warning!!!! */
#define dst	info.rti_info[RTAX_DST]
#define gate	info.rti_info[RTAX_GATEWAY]
#define netmask	info.rti_info[RTAX_NETMASK]
#define genmask	info.rti_info[RTAX_GENMASK]
#define ifpaddr	info.rti_info[RTAX_IFP]
#define ifaaddr	info.rti_info[RTAX_IFA]
#define brdaddr	info.rti_info[RTAX_BRD]


/*******************************************************************************
* rtSockInit - intialize route sockets
*
* This function initializes the route msg hooks used in various places in the
* system. The hooks are provided to scale out route sockets. This function
* is called through the domain_init entry point of the route socket domain.
*
* RETURNS: N/A
*
* NOMANUAL
*/

LOCAL void rtSockInit (void)
    {
    _rtMissMsgHook	= rt_missmsg;	 /* route miss message hook */
    _rtIfaceMsgHook	= rt_ifmsg;	 /* netwk interface msg hook */
    _rtNewAddrMsgHook	= rt_newaddrmsg; /* new address msg hook */

    raw_init ();     			 /* initialize the raw control block */
    }
    
/*ARGSUSED*/
static int
route_usrreq(so, req, m, nam, control)
	register struct socket *so;
	int req;
	struct mbuf *m, *nam, *control;
{
	register int error = 0;
	register struct rawcb *rp = sotorawcb(so);
	int s;

	if (req == PRU_ATTACH) {
		MALLOC(rp, struct rawcb *, sizeof(*rp), MT_PCB, M_WAIT);
		if (rp == (struct rawcb *) NULL)
		    {
		    return (ENOBUFS);
		    }
		if ((so->so_pcb = (caddr_t)rp))
			bzero(so->so_pcb, sizeof(*rp));

	}
	if (req == PRU_DETACH && rp) {
		int af = rp->rcb_proto.sp_protocol;
		if (af == AF_INET)
			route_cb.ip_count--;
		else if (af == AF_NS)
			route_cb.ns_count--;
		else if (af == AF_ISO)
			route_cb.iso_count--;
		route_cb.any_count--;
	}
	s = splnet();
	error = raw_usrreq(so, req, m, nam, control);
	rp = sotorawcb(so);
	if (req == PRU_ATTACH && rp) {
		int af = rp->rcb_proto.sp_protocol;
		if (error) {
			FREE(rp, MT_PCB);
			splx(s);
			return (error);
		}
		if (af == AF_INET)
			route_cb.ip_count++;
		else if (af == AF_NS)
			route_cb.ns_count++;
		else if (af == AF_ISO)
			route_cb.iso_count++;
		rp->rcb_faddr = &route_src;
		route_cb.any_count++;
		soisconnected(so);
		so->so_options |= SO_USELOOPBACK;
	}
	splx(s);
	return (error);
}

/*ARGSUSED*/
static int
route_output(m, so)
	register struct mbuf *m;
	struct socket *so;
{
	register struct rt_msghdr *rtm = 0;
	register struct rtentry *rt = 0;
	struct rtentry *saved_nrt = 0;
	struct radix_node_head *rnh;
	struct rt_addrinfo info;
	int len, error = 0;
	struct ifnet *ifp = 0;
	struct ifaddr *ifa = 0;

#define senderr(e) { error = e; goto flush;}
	if (m == 0 || ((m->m_len < sizeof(long)) &&
		       (m = m_pullup(m, sizeof(long))) == 0))
		return (ENOBUFS);
	if ((m->m_flags & M_PKTHDR) == 0)
		panic("route_output");
	len = m->m_pkthdr.len;
	if (len < sizeof(*rtm) ||
	    len != mtod(m, struct rt_msghdr *)->rtm_msglen) {
		dst = 0;
		senderr(EINVAL);
	}
	R_Malloc(rtm, struct rt_msghdr *, len);
	if (rtm == 0) {
		dst = 0;
		senderr(ENOBUFS);
	}
	m_copydata(m, 0, len, (caddr_t)rtm);
	if (rtm->rtm_version != RTM_VERSION) {
		dst = 0;
		senderr(EPROTONOSUPPORT);
	}
	info.rti_addrs = rtm->rtm_addrs;
	rt_xaddrs((caddr_t)(rtm + 1), len + (caddr_t)rtm, &info);
	if (dst == 0)
		senderr(EINVAL);
	if (genmask) {
		struct radix_node *t;
		t = rn_addmask((caddr_t)genmask, 0, 1);
		if (t && Bcmp(genmask, t->rn_key, *(u_char *)genmask) == 0)
			genmask = (struct sockaddr *)(t->rn_key);
		else
			senderr(ENOBUFS);
	}
	switch (rtm->rtm_type) {

	case RTM_ADD:
		if (gate == 0)
			senderr(EINVAL);

                error = rtrequestAddEqui(dst, netmask, gate, rtm->rtm_flags,
					 M2_ipRouteProto_other, &saved_nrt);
		if (error == 0 && saved_nrt) {
			rt_setmetrics(rtm->rtm_inits,
				&rtm->rtm_rmx, &saved_nrt->rt_rmx);
			saved_nrt->rt_refcnt--;
			saved_nrt->rt_genmask = genmask;
		}
		break;

	case RTM_DELETE:
                error = rtrequestDelEqui(dst, netmask, gate, rtm->rtm_flags,
					 M2_ipRouteProto_other, &saved_nrt);
		if (error == 0) {
			(rt = saved_nrt)->rt_refcnt++;
			goto report;
		}
		break;

	case RTM_GET:
	case RTM_CHANGE:
	case RTM_LOCK:
		if ((rnh = rt_tables[dst->sa_family]) == 0) {
			senderr(EAFNOSUPPORT);
		} else if ((rt = (struct rtentry *)
				rnh->rnh_lookup(dst, netmask, rnh)))
			rt->rt_refcnt++;
		else
			senderr(ESRCH);
		switch(rtm->rtm_type) {

		case RTM_GET:
		report:
			dst = rt_key(rt);
			gate = rt->rt_gateway;
			netmask = rt_mask(rt);
			genmask = rt->rt_genmask;
			if ((rtm->rtm_addrs & (RTA_IFP | RTA_IFA))) {
				if ((ifp = rt->rt_ifp)) {
					ifpaddr = ifp->if_addrlist->ifa_addr;
					ifaaddr = rt->rt_ifa->ifa_addr;
					if (ifp->if_flags & IFF_POINTOPOINT)
						brdaddr = rt->rt_ifa->ifa_dstaddr;
					else
						brdaddr = 0;
					rtm->rtm_index = ifp->if_index;
				} else {
					ifpaddr = 0;
					ifaaddr = 0;
			    }
			}
			len = rt_msg2(rtm->rtm_type, &info, (caddr_t)0,
				(struct walkarg *)0);
			if (len > rtm->rtm_msglen) {
				struct rt_msghdr *new_rtm;
				R_Malloc(new_rtm, struct rt_msghdr *, len);
				if (new_rtm == 0)
					senderr(ENOBUFS);
				Bcopy(rtm, new_rtm, rtm->rtm_msglen);
				Free(rtm); rtm = new_rtm;
			}
			(void)rt_msg2(rtm->rtm_type, &info, (caddr_t)rtm,
				(struct walkarg *)0);
			rtm->rtm_flags = rt->rt_flags;
			rtm->rtm_rmx = rt->rt_rmx;
			rtm->rtm_addrs = info.rti_addrs;
			break;

		case RTM_CHANGE:
			if (gate && rt_setgate(rt, rt_key(rt), gate))
				senderr(ENOSPC);
			/* new gateway could require new ifaddr, ifp;
			   flags may also be different; ifp may be specified
			   by ll sockaddr when protocol address is ambiguous */
			if (ifpaddr && (ifa = ifa_ifwithnet(ifpaddr)) &&
			    (ifp = ifa->ifa_ifp))
				ifa = ifaof_ifpforaddr(ifaaddr ? ifaaddr : gate,
							ifp);
			else if ((ifaaddr && (ifa = ifa_ifwithaddr(ifaaddr))) ||
				 (ifa = ifa_ifwithroute(rt->rt_flags,
							rt_key(rt), gate)))
				ifp = ifa->ifa_ifp;
			if (ifa) {
				register struct ifaddr *oifa = rt->rt_ifa;
				if (oifa != ifa) {
				    if (oifa && oifa->ifa_rtrequest)
					oifa->ifa_rtrequest(RTM_DELETE,
								rt, gate);
				    IFAFREE(rt->rt_ifa);
				    rt->rt_ifa = ifa;
				    ifa->ifa_refcnt++;
				    rt->rt_ifp = ifp;
				}
			}
			rt_setmetrics(rtm->rtm_inits, &rtm->rtm_rmx,
					&rt->rt_rmx);
			if (rt->rt_ifa && rt->rt_ifa->ifa_rtrequest)
			       rt->rt_ifa->ifa_rtrequest(RTM_ADD, rt, gate);
			if (genmask)
				rt->rt_genmask = genmask;
			/*
			 * Fall into
			 */
		case RTM_LOCK:
			rt->rt_rmx.rmx_locks &= ~(rtm->rtm_inits);
			rt->rt_rmx.rmx_locks |=
				(rtm->rtm_inits & rtm->rtm_rmx.rmx_locks);
			break;
		}
		break;

	default:
		senderr(EOPNOTSUPP);
	}

flush:
	if (rtm) {
		if (error)
			rtm->rtm_errno = error;
		else 
			rtm->rtm_flags |= RTF_DONE;
	}
	if (rt)
		rtfree(rt);
    {
	register struct rawcb *rp = 0;
	/*
	 * Check to see if we don't want our own messages.
	 */
	if ((so->so_options & SO_USELOOPBACK) == 0) {
		if (route_cb.any_count <= 1) {
			if (rtm)
				Free(rtm);
			m_freem(m);
			return (error);
		}
		/* There is another listener, so construct message */
		rp = sotorawcb(so);
	}
	if (rtm) {
		m_copyback(m, 0, rtm->rtm_msglen, (caddr_t)rtm);
		Free(rtm);
	}
	if (rp)
		rp->rcb_proto.sp_family = 0; /* Avoid us */
	if (dst)
		route_proto.sp_protocol = dst->sa_family;
	raw_input(m, &route_proto, &route_src, &route_dst);
	if (rp)
		rp->rcb_proto.sp_family = PF_ROUTE;
    }
	return (error);
}

static void
rt_setmetrics(which, in, out)
	u_long which;
	register struct rt_metrics *in, *out;
{
#define metric(f, e) if (which & (f)) out->e = in->e;
	metric(RTV_RPIPE, rmx_recvpipe);
	metric(RTV_SPIPE, rmx_sendpipe);
	metric(RTV_SSTHRESH, rmx_ssthresh);
	metric(RTV_RTT, rmx_rtt);
	metric(RTV_RTTVAR, rmx_rttvar);
	metric(RTV_HOPCOUNT, rmx_hopcount);
	metric(RTV_MTU, rmx_mtu);
	metric(RTV_EXPIRE, rmx_expire);
#undef metric
}

#define ROUNDUP(a) \
	((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
#define ADVANCE(x, n) (x += ROUNDUP((n)->sa_len))

static void
rt_xaddrs(cp, cplim, rtinfo)
	register caddr_t cp, cplim;
	register struct rt_addrinfo *rtinfo;
{
	register struct sockaddr *sa;
	register int i;

	bzero((char *)rtinfo->rti_info, sizeof(rtinfo->rti_info));
	for (i = 0; (i < RTAX_MAX) && (cp < cplim); i++) {
		if ((rtinfo->rti_addrs & (1 << i)) == 0)
			continue;
		rtinfo->rti_info[i] = sa = (struct sockaddr *)cp;
		ADVANCE(cp, sa);
	}
}

static struct mbuf *
rt_msg1(type, rtinfo)
	int type;
	register struct rt_addrinfo *rtinfo;
{
	register struct rt_msghdr *rtm;
	register struct mbuf *m;
	register int i;
	register struct sockaddr *sa;
	int len, dlen;

	m = mHdrClGet(M_DONTWAIT, MT_DATA, CL_SIZE_128, TRUE);
	if (m == 0)
		return (m);
	switch (type) {

	case RTM_DELADDR:
	case RTM_NEWADDR:
		len = sizeof(struct ifa_msghdr);
		break;

	case RTM_IFINFO:
		len = sizeof(struct if_msghdr);
		break;

	default:
		len = sizeof(struct rt_msghdr);
	}
	if (len > m->m_extSize)
		panic("rt_msg1");
	m->m_pkthdr.len = m->m_len = len;
	m->m_pkthdr.rcvif = 0;
	rtm = mtod(m, struct rt_msghdr *);
	bzero((caddr_t)rtm, len);
	for (i = 0; i < RTAX_MAX; i++) {
		if ((sa = rtinfo->rti_info[i]) == NULL)
			continue;
		rtinfo->rti_addrs |= (1 << i);
		dlen = ROUNDUP(sa->sa_len);
		m_copyback(m, len, dlen, (caddr_t)sa);
		len += dlen;
	}
	if (m->m_pkthdr.len != len) {
		m_freem(m);
		return (NULL);
	}
	rtm->rtm_msglen = len;
	rtm->rtm_version = RTM_VERSION;
	rtm->rtm_type = type;
	return (m);
}

static int
rt_msg2(type, rtinfo, cp, w)
	int type;
	register struct rt_addrinfo *rtinfo;
	caddr_t cp;
	struct walkarg *w;
{
	register int i;
	int len, dlen, second_time = 0;
	caddr_t cp0;

	rtinfo->rti_addrs = 0;
again:
	switch (type) {

	case RTM_DELADDR:
	case RTM_NEWADDR:
		len = sizeof(struct ifa_msghdr);
		break;

	case RTM_IFINFO:
		len = sizeof(struct if_msghdr);
		break;

	default:
		len = sizeof(struct rt_msghdr);
	}
	if ((cp0 = cp))
		cp += len;
	for (i = 0; i < RTAX_MAX; i++) {
		register struct sockaddr *sa;

		if ((sa = rtinfo->rti_info[i]) == 0)
			continue;
		rtinfo->rti_addrs |= (1 << i);
		dlen = ROUNDUP(sa->sa_len);
		if (cp) {
			bcopy((caddr_t)sa, cp, (unsigned)dlen);
			cp += dlen;
		}
		len += dlen;
	}
	if (cp == 0 && w != NULL && !second_time) {
		register struct walkarg *rw = w;

		rw->w_needed += len;
		if (rw->w_needed <= 0 && rw->w_where) {
			if (rw->w_tmemsize < len) {
				if (rw->w_tmem)
				        {
					FREE(rw->w_tmem, MT_RTABLE);
					}
				MALLOC(rw->w_tmem, caddr_t, len, MT_RTABLE,
				       M_DONTWAIT); 
				if (rw->w_tmem)
					rw->w_tmemsize = len;
			}
			if (rw->w_tmem) {
				cp = rw->w_tmem;
				second_time = 1;
				goto again;
			} else
				rw->w_where = 0;
		}
	}
	if (cp) {
		register struct rt_msghdr *rtm = (struct rt_msghdr *)cp0;

		rtm->rtm_version = RTM_VERSION;
		rtm->rtm_type = type;
		rtm->rtm_msglen = len;
	}
	return (len);
}

/*
 * This routine is called to generate a message from the routing
 * socket indicating that a redirect has occured, a routing lookup
 * has failed, or that a protocol has detected timeouts to a particular
 * destination.
 */
static void
rt_missmsg(type, rtinfo, flags, error)
	int type, flags, error;
	register struct rt_addrinfo *rtinfo;
{
	register struct rt_msghdr *rtm;
	register struct mbuf *m;
	struct sockaddr *sa = rtinfo->rti_info[RTAX_DST];

	if (route_cb.any_count == 0)
		return;
	m = rt_msg1(type, rtinfo);
	if (m == 0)
		return;
	rtm = mtod(m, struct rt_msghdr *);
	rtm->rtm_flags = RTF_DONE | flags;
	rtm->rtm_errno = error;
	rtm->rtm_addrs = rtinfo->rti_addrs;
	route_proto.sp_protocol = sa ? sa->sa_family : 0;
	raw_input(m, &route_proto, &route_src, &route_dst);
}

/*
 * This routine is called to generate a message from the routing
 * socket indicating that the status of a network interface has changed.
 */
static void
rt_ifmsg(ifp)
	register struct ifnet *ifp;
{
	register struct if_msghdr *ifm;
	struct mbuf *m;
	struct rt_addrinfo info;

	if (route_cb.any_count == 0)
		return;
	bzero((caddr_t)&info, sizeof(info));
	m = rt_msg1(RTM_IFINFO, &info);
	if (m == 0)
		return;
	ifm = mtod(m, struct if_msghdr *);
	ifm->ifm_index = ifp->if_index;
	ifm->ifm_flags = ifp->if_flags;
	ifm->ifm_data = ifp->if_data;
	ifm->ifm_addrs = 0;
	route_proto.sp_protocol = 0;
	raw_input(m, &route_proto, &route_src, &route_dst);
}

/*
 * This is called to generate messages from the routing socket
 * indicating a network interface has had addresses associated with it.
 * if we ever reverse the logic and replace messages TO the routing
 * socket indicate a request to configure interfaces, then it will
 * be unnecessary as the routing socket will automatically generate
 * copies of it.
 */
static void
rt_newaddrmsg(cmd, ifa, error, rt)
	int cmd, error;
	register struct ifaddr *ifa;
	register struct rtentry *rt;
{
	struct rt_addrinfo info;
	struct sockaddr *sa = NULL;
	int pass;
	struct mbuf *m = NULL;
	struct ifnet *ifp = ifa->ifa_ifp;

	if (route_cb.any_count == 0)
		return;
	for (pass = 1; pass < 3; pass++) {
		bzero((caddr_t)&info, sizeof(info));
		if ((cmd == RTM_ADD && pass == 1) ||
		    (cmd == RTM_DELETE && pass == 2)) {
			register struct ifa_msghdr *ifam;
			int ncmd = cmd == RTM_ADD ? RTM_NEWADDR : RTM_DELADDR;

			ifaaddr = sa = ifa->ifa_addr;
			ifpaddr = ifp->if_addrlist->ifa_addr;
			netmask = ifa->ifa_netmask;
			brdaddr = ifa->ifa_dstaddr;
			if ((m = rt_msg1(ncmd, &info)) == NULL)
				continue;
			ifam = mtod(m, struct ifa_msghdr *);
			ifam->ifam_index = ifp->if_index;
			ifam->ifam_metric = ifa->ifa_metric;
			ifam->ifam_flags = ifa->ifa_flags;
			ifam->ifam_addrs = info.rti_addrs;
		}
		if ((cmd == RTM_ADD && pass == 2) ||
		    (cmd == RTM_DELETE && pass == 1)) {
			register struct rt_msghdr *rtm;
			
			if (rt == 0)
				continue;
			netmask = rt_mask(rt);
			dst = sa = rt_key(rt);
			gate = rt->rt_gateway;
			if ((m = rt_msg1(cmd, &info)) == NULL)
				continue;
			rtm = mtod(m, struct rt_msghdr *);
			rtm->rtm_index = ifp->if_index;
			rtm->rtm_flags |= rt->rt_flags;
			rtm->rtm_errno = error;
			rtm->rtm_addrs = info.rti_addrs;
		}
		route_proto.sp_protocol = sa ? sa->sa_family : 0;
		raw_input(m, &route_proto, &route_src, &route_dst);
	}
}

/*
 * This is used in dumping the kernel table via sysctl().
 */
int
sysctl_dumpentry(rn, w)
	struct radix_node *rn;
	register struct walkarg *w;
{
	register struct rtentry *rt = (struct rtentry *)rn;
	int error = 0, size;
	struct rt_addrinfo info;

	if (w->w_op == NET_RT_FLAGS && !(rt->rt_flags & w->w_arg))
		return 0;
	bzero((caddr_t)&info, sizeof(info));
	dst = rt_key(rt);
	gate = rt->rt_gateway;
	netmask = rt_mask(rt);
	genmask = rt->rt_genmask;
	if (rt->rt_ifp) {
		ifpaddr = rt->rt_ifp->if_addrlist->ifa_addr;
		ifaaddr = rt->rt_ifa->ifa_addr;
		if (rt->rt_ifp->if_flags & IFF_POINTOPOINT)
			brdaddr = rt->rt_ifa->ifa_dstaddr;
	}
	size = rt_msg2(RTM_GET, &info, 0, w);
	if (w->w_where && w->w_tmem) {
		register struct rt_msghdr *rtm = (struct rt_msghdr *)w->w_tmem;

		rtm->rtm_flags = rt->rt_flags;
		rtm->rtm_use = rt->rt_use;
		rtm->rtm_rmx = rt->rt_rmx;
		rtm->rtm_index = rt->rt_ifp->if_index;
		rtm->rtm_errno = rtm->rtm_pid = rtm->rtm_seq = 0;
		rtm->rtm_addrs = info.rti_addrs;
		if ((error = copyout((caddr_t)rtm, w->w_where, size)))
			w->w_where = NULL;
		else
			w->w_where += size;
	}
	return (error);
}

int
sysctl_iflist(af, w)
	int	af;
	register struct	walkarg *w;
{
	register struct ifnet *ifp;
	register struct ifaddr *ifa;
	struct	rt_addrinfo info;
	int	len, error = 0;

	bzero((caddr_t)&info, sizeof(info));
	for (ifp = ifnet; ifp; ifp = ifp->if_next) {
		if (w->w_arg && w->w_arg != ifp->if_index)
			continue;
		ifa = ifp->if_addrlist;
		ifpaddr = ifa->ifa_addr;
		len = rt_msg2(RTM_IFINFO, &info, (caddr_t)0, w);
		ifpaddr = 0;
		if (w->w_where && w->w_tmem) {
			register struct if_msghdr *ifm;

			ifm = (struct if_msghdr *)w->w_tmem;
			ifm->ifm_index = ifp->if_index;
			ifm->ifm_flags = ifp->if_flags;
			ifm->ifm_data = ifp->if_data;
			ifm->ifm_addrs = info.rti_addrs;
			if ((error = copyout((caddr_t)ifm, w->w_where, len)))
				return (error);
			w->w_where += len;
		}
		while ((ifa = ifa->ifa_next)) {
			if (af && af != ifa->ifa_addr->sa_family)
				continue;
			ifaaddr = ifa->ifa_addr;
			netmask = ifa->ifa_netmask;
			brdaddr = ifa->ifa_dstaddr;
			len = rt_msg2(RTM_NEWADDR, &info, 0, w);
			if (w->w_where && w->w_tmem) {
				register struct ifa_msghdr *ifam;

				ifam = (struct ifa_msghdr *)w->w_tmem;
				ifam->ifam_index = ifa->ifa_ifp->if_index;
				ifam->ifam_flags = ifa->ifa_flags;
				ifam->ifam_metric = ifa->ifa_metric;
				ifam->ifam_addrs = info.rti_addrs;
				if ((error = copyout(w->w_tmem, w->w_where,
                                                     len)))
					return (error);
				w->w_where += len;
			}
		}
		ifaaddr = netmask = brdaddr = 0;
	}
	return (0);
}

int
sysctl_rtable(name, namelen, where, given, new, newlen)
	int	*name;
	int	namelen;
	caddr_t	where;
	size_t	*given;
	caddr_t	*new;
	size_t	newlen;
{
	register struct radix_node_head *rnh;
	int	i, s, error = EINVAL;
	u_char  af;
	struct	walkarg w;

	if (new)
		return (EPERM);
	if (namelen != 3)
		return (EINVAL);
	af = name[0];
	Bzero(&w, sizeof(w));
	w.w_where = where;
	w.w_given = *given;
	w.w_needed = 0 - w.w_given;
	w.w_op = name[1];
	w.w_arg = name[2];

	s = splnet();
	switch (w.w_op) {

	case NET_RT_DUMP:
	case NET_RT_FLAGS:
		for (i = 1; i <= AF_MAX; i++)
			if ((rnh = rt_tables[i]) && (af == 0 || af == i) &&
			    (error = rnh->rnh_walktree(rnh,
							sysctl_dumpentry, &w)))
				break;
		break;

	case NET_RT_IFLIST:
		error = sysctl_iflist(af, &w);
	}
	splx(s);
	if (w.w_tmem){
		FREE(w.w_tmem, MT_RTABLE);
	}
	w.w_needed += w.w_given;
	if (where) {
		*given = w.w_where - where;
		if (*given < w.w_needed)
			return (ENOMEM);
	} else {
		*given = (11 * w.w_needed) / 10;
	}
	return (error);
}

/*
 * Definitions of protocols supported in the ROUTE domain.
 */
extern	struct domain routedomain;		/* or at least forward */

struct protosw routesw[] = {
{ SOCK_RAW,	&routedomain,	0,		PR_ATOMIC|PR_ADDR,
  raw_input,	route_output,	raw_ctlinput,	0,
  route_usrreq,
  rtSockInit,	0,		0,		0,
  sysctl_rtable,
}
};

struct domain routedomain =
    { PF_ROUTE, "route", 0, 0, 0,
      routesw, &routesw[sizeof(routesw)/sizeof(routesw[0])] };

/*
 * Copy data from a buffer back into the indicated mbuf chain,
 * starting "off" bytes from the beginning, extending the mbuf
 * chain if necessary.
 */
static void
m_copyback(m0, off, len, cp)
	struct	mbuf *m0;
	register int off;
	register int len;
	caddr_t cp;
{
	register int mlen;
	register struct mbuf *m = m0, *n;
	int totlen = 0;

	if (m0 == 0)
		return;
	while (off > (mlen = m->m_len)) {
		off -= mlen;
		totlen += mlen;
		if (m->m_next == 0) {
			n = m_getclr(M_DONTWAIT, m->m_type, CL_SIZE_128, TRUE);
			if (n == 0)
				goto out;
			n->m_len = min(n->m_extSize, len + off);
			m->m_next = n;
		}
		m = m->m_next;
	}
	while (len > 0) {
		mlen = min (m->m_len - off, len);
		bcopy(cp, off + mtod(m, caddr_t), (unsigned)mlen);
		cp += mlen;
		len -= mlen;
		mlen += off;
		off = 0;
		totlen += mlen;
		if (len == 0)
			break;
		if (m->m_next == 0) {
			n = mBufClGet(M_DONTWAIT, m->m_type, CL_SIZE_128, TRUE);
			if (n == 0)
				break;
			n->m_len = min(n->m_extSize, len);
			m->m_next = n;
		}
		m = m->m_next;
	}
out:	if (((m = m0)->m_flags & M_PKTHDR) && (m->m_pkthdr.len < totlen))
		m->m_pkthdr.len = totlen;
}

/*******************************************************************************
*
* m_copydata - copy data from an mbuf chain into a buff
* Copy data from an mbuf chain starting "off" bytes from the beginning,
* continuing for "len" bytes, into the indicated buffer.
*/
static void m_copydata(m, off, len, cp)
    register struct mbuf *m;
    register int off;
    register int len;
    caddr_t cp;
    {
    register unsigned count;

    if (off < 0 || len < 0)
	panic("m_copydata");
    while (off > 0)
	{
	if (m == 0)
	    panic("m_copydata");
	if (off < m->m_len)
	    break;
	off -= m->m_len;
	m = m->m_next;
	}
    while (len > 0)
	{
	if (m == 0)
	    panic("m_copydata");
	count = min(m->m_len - off, len);
	bcopy(mtod(m, caddr_t) + off, cp, count);
	len -= count;
	cp += count;
	off = 0;
	m = m->m_next;
	}
    }