/*
 * |-----------------------------------------------------------|
 * | Copyright (c) 1991, 1990 MIPS Computer Systems, Inc.      |
 * | All Rights Reserved                                       |
 * |-----------------------------------------------------------|
 * |          Restricted Rights Legend                         |
 * | Use, duplication, or disclosure by the Government is      |
 * | subject to restrictions as set forth in                   |
 * | subparagraph (c)(1)(ii) of the Rights in Technical        |
 * | Data and Computer Software Clause of DFARS 252.227-7013.  |
 * |         MIPS Computer Systems, Inc.                       |
 * |         950 DeGuigne Avenue                               |
 * |         Sunnyvale, California 94088-3650, USA             |
 * |-----------------------------------------------------------|
 */
#ident	"$Header: if.c,v 1.9.2.1 92/06/24 13:40:44 marker Exp $"

/*
 * Copyright (c) 1983 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that: (1) source distributions retain this entire copyright
 * notice and comment, and (2) distributions including binaries display
 * the following acknowledgement:  ``This product includes software
 * developed by the University of California, Berkeley and its contributors''
 * in the documentation or other materials provided with the distribution
 * and in all advertising materials mentioning features or use of this
 * software. 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef lint
static char sccsid[] = "@(#)if.c	5.6 (Berkeley) 6/1/90";
#endif /* not lint */

/*
 * 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) \
	(bcmp((caddr_t)((a1)->sa_data), (caddr_t)((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);
}
