freebsd-skq/usr.sbin/routed/if.c
1995-05-30 03:57:47 +00:00

149 lines
4.2 KiB
C

/*
* 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 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.
*/
#ifndef lint
static char sccsid[] = "@(#)if.c 8.1 (Berkeley) 6/5/93";
#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);
}