if.c   [plain text]


/*
 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * "Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
 * Reserved.  This file contains Original Code and/or Modifications of
 * Original Code as defined in and that are subject to the Apple Public
 * Source License Version 1.0 (the 'License').  You may not use this file
 * except in compliance with the License.  Please obtain a copy of the
 * License at http://www.apple.com/publicsource and read it before using
 * this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License."
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*
 * Copyright (c) 1983, 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 acknowledgment:
 *	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.
 *
 *	@(#)defs.h	8.1 (Berkeley) 6/5/93
 */


/*
 * Routing Table Management Daemon
 */
#include "defs.h"

extern	struct interface *ifnet;

/*
 * Find the interface with address addr.
 */
struct interface *
if_ifwithaddr(addr)
	struct sockaddr *addr;
{
	register struct interface *ifp;

#define	same(a1, a2) \
	(memcmp((a1)->sa_data, (a2)->sa_data, 14) == 0)
	for (ifp = ifnet; ifp; ifp = ifp->int_next) {
		if (ifp->int_flags & IFF_REMOTE)
			continue;
		if (ifp->int_addr.sa_family != addr->sa_family)
			continue;
		if (same(&ifp->int_addr, addr))
			break;
		if ((ifp->int_flags & IFF_BROADCAST) &&
		    same(&ifp->int_broadaddr, addr))
			break;
	}
	return (ifp);
}

/*
 * Find the point-to-point interface with destination address addr.
 */
struct interface *
if_ifwithdstaddr(addr)
	struct sockaddr *addr;
{
	register struct interface *ifp;

	for (ifp = ifnet; ifp; ifp = ifp->int_next) {
		if ((ifp->int_flags & IFF_POINTOPOINT) == 0)
			continue;
		if (same(&ifp->int_dstaddr, addr))
			break;
	}
	return (ifp);
}

/*
 * Find the interface on the network 
 * of the specified address.
 */
struct interface *
if_ifwithnet(addr)
	register struct sockaddr *addr;
{
	register struct interface *ifp;
	register int af = addr->sa_family;
	register int (*netmatch)();

	if (af >= af_max)
		return (0);
	netmatch = afswitch[af].af_netmatch;
	for (ifp = ifnet; ifp; ifp = ifp->int_next) {
		if (ifp->int_flags & IFF_REMOTE)
			continue;
		if (af != ifp->int_addr.sa_family)
			continue;
		if ((*netmatch)(addr, &ifp->int_addr))
			break;
	}
	return (ifp);
}

/*
 * Find an interface from which the specified address
 * should have come from.  Used for figuring out which
 * interface a packet came in on -- for tracing.
 */
struct interface *
if_iflookup(addr)
	struct sockaddr *addr;
{
	register struct interface *ifp, *maybe;
	register int af = addr->sa_family;
	register int (*netmatch)();

	if (af >= af_max)
		return (0);
	maybe = 0;
	netmatch = afswitch[af].af_netmatch;
	for (ifp = ifnet; ifp; ifp = ifp->int_next) {
		if (ifp->int_addr.sa_family != af)
			continue;
		if (same(&ifp->int_addr, addr))
			break;
		if ((ifp->int_flags & IFF_BROADCAST) &&
		    same(&ifp->int_broadaddr, addr))
			break;
		if ((ifp->int_flags & IFF_POINTOPOINT) &&
		    same(&ifp->int_dstaddr, addr))
			break;
		if (maybe == 0 && (*netmatch)(addr, &ifp->int_addr))
			maybe = ifp;
	}
	if (ifp == 0)
		ifp = maybe;
	return (ifp);
}