usr.sbin/IPXrouted/if.c

   1 /*
   2  * Copyright (c) 1983, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Copyright (c) 1995 John Hay.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by the University of
  18  *      California, Berkeley and its contributors.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  * static char sccsid[] = "@(#)if.c     5.1 (Berkeley) 6/4/85"; (routed/if.c)
  36  *
  37  * $FreeBSD: src/usr.sbin/IPXrouted/if.c,v 1.5 1999/08/28 01:15:02 peter Exp $
  38  * $DragonFly: src/usr.sbin/IPXrouted/if.c,v 1.3 2004/03/11 09:38:59 hmp Exp $
  39  *
  40  * @(#)if.c     8.1 (Berkeley) 6/5/93
  41  */
  42
  43 /*
  44  * Routing Table Management Daemon
  45  */
  46 #include "defs.h"
  47
  48 extern  struct interface *ifnet;
  49
  50 /*
  51  * Find the interface with address addr.
  52  */
  53 struct interface *
  54 if_ifwithaddr(struct sockaddr *addr)
  55 {
  56         struct interface *ifp;
  57
  58 #define same(a1, a2) \
  59         (bcmp((caddr_t)((a1)->sa_data), (caddr_t)((a2)->sa_data), 10) == 0)
  60         for (ifp = ifnet; ifp; ifp = ifp->int_next) {
  61                 if (ifp->int_flags & IFF_REMOTE)
  62                         continue;
  63                 if (ifp->int_addr.sa_family != addr->sa_family)
  64                         continue;
  65                 if (same(&ifp->int_addr, addr))
  66                         break;
  67                 if ((ifp->int_flags & IFF_BROADCAST) &&
  68                     same(&ifp->int_broadaddr, addr))
  69                         break;
  70         }
  71         return (ifp);
  72 }
  73
  74 /*
  75  * Find the point-to-point interface with destination address addr.
  76  */
  77 struct interface *
  78 if_ifwithdstaddr(struct sockaddr *addr)
  79 {
  80         struct interface *ifp;
  81
  82         for (ifp = ifnet; ifp; ifp = ifp->int_next) {
  83                 if ((ifp->int_flags & IFF_POINTOPOINT) == 0)
  84                         continue;
  85                 if (same(&ifp->int_dstaddr, addr))
  86                         break;
  87         }
  88         return (ifp);
  89 }
  90
  91 /*
  92  * Find the interface on the network
  93  * of the specified address.
  94  */
  95 struct interface *
  96 if_ifwithnet(struct sockaddr *addr)
  97 {
  98         struct interface *ifp;
  99         int af = addr->sa_family;
 100         int (*netmatch)();
 101
 102         if (af >= AF_MAX)
 103                 return (0);
 104         netmatch = afswitch[af].af_netmatch;
 105         for (ifp = ifnet; ifp; ifp = ifp->int_next) {
 106                 if (ifp->int_flags & IFF_REMOTE)
 107                         continue;
 108                 if (af != ifp->int_addr.sa_family)
 109                         continue;
 110                 if ((*netmatch)(addr, &ifp->int_addr))
 111                         break;
 112         }
 113         return (ifp);
 114 }
 115
 116 /*
 117  * Find an interface from which the specified address
 118  * should have come from.  Used for figuring out which
 119  * interface a packet came in on -- for tracing.
 120  */
 121 struct interface *
 122 if_iflookup(struct sockaddr *addr)
 123 {
 124         struct interface *ifp, *maybe;
 125         int af = addr->sa_family;
 126         int (*netmatch)();
 127
 128         if (af >= AF_MAX)
 129                 return (0);
 130         maybe = 0;
 131         netmatch = afswitch[af].af_netmatch;
 132         for (ifp = ifnet; ifp; ifp = ifp->int_next) {
 133                 if (ifp->int_addr.sa_family != af)
 134                         continue;
 135                 if (same(&ifp->int_addr, addr))
 136                         break;
 137                 if ((ifp->int_flags & IFF_BROADCAST) &&
 138                     same(&ifp->int_broadaddr, addr))
 139                         break;
 140                 if (maybe == 0 && (*netmatch)(addr, &ifp->int_addr))
 141                         maybe = ifp;
 142         }
 143         if (ifp == 0)
 144                 ifp = maybe;
 145         return (ifp);
 146 }