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  * $FreeBSD$
  38  */
  39
  40 #ifndef lint
  41 static const char sccsid[] = "@(#)if.c  8.1 (Berkeley) 6/5/93";
  42 #endif /* not lint */
  43
  44 /*
  45  * Routing Table Management Daemon
  46  */
  47 #include "defs.h"
  48
  49 extern  struct interface *ifnet;
  50
  51 /*
  52  * Find the interface with address addr.
  53  */
  54 struct interface *
  55 if_ifwithaddr(addr)
  56         struct sockaddr *addr;
  57 {
  58         register struct interface *ifp;
  59
  60 #define same(a1, a2) \
  61         (bcmp((caddr_t)((a1)->sa_data), (caddr_t)((a2)->sa_data), 10) == 0)
  62         for (ifp = ifnet; ifp; ifp = ifp->int_next) {
  63                 if (ifp->int_flags & IFF_REMOTE)
  64                         continue;
  65                 if (ifp->int_addr.sa_family != addr->sa_family)
  66                         continue;
  67                 if (same(&ifp->int_addr, addr))
  68                         break;
  69                 if ((ifp->int_flags & IFF_BROADCAST) &&
  70                     same(&ifp->int_broadaddr, addr))
  71                         break;
  72         }
  73         return (ifp);
  74 }
  75
  76 /*
  77  * Find the point-to-point interface with destination address addr.
  78  */
  79 struct interface *
  80 if_ifwithdstaddr(addr)
  81         struct sockaddr *addr;
  82 {
  83         register struct interface *ifp;
  84
  85         for (ifp = ifnet; ifp; ifp = ifp->int_next) {
  86                 if ((ifp->int_flags & IFF_POINTOPOINT) == 0)
  87                         continue;
  88                 if (same(&ifp->int_dstaddr, addr))
  89                         break;
  90         }
  91         return (ifp);
  92 }
  93
  94 /*
  95  * Find the interface on the network
  96  * of the specified address.
  97  */
  98 struct interface *
  99 if_ifwithnet(addr)
 100         register struct sockaddr *addr;
 101 {
 102         register struct interface *ifp;
 103         register int af = addr->sa_family;
 104         register int (*netmatch)();
 105
 106         if (af >= AF_MAX)
 107                 return (0);
 108         netmatch = afswitch[af].af_netmatch;
 109         for (ifp = ifnet; ifp; ifp = ifp->int_next) {
 110                 if (ifp->int_flags & IFF_REMOTE)
 111                         continue;
 112                 if (af != ifp->int_addr.sa_family)
 113                         continue;
 114                 if ((*netmatch)(addr, &ifp->int_addr))
 115                         break;
 116         }
 117         return (ifp);
 118 }
 119
 120 /*
 121  * Find an interface from which the specified address
 122  * should have come from.  Used for figuring out which
 123  * interface a packet came in on -- for tracing.
 124  */
 125 struct interface *
 126 if_iflookup(addr)
 127         struct sockaddr *addr;
 128 {
 129         register struct interface *ifp, *maybe;
 130         register int af = addr->sa_family;
 131         register int (*netmatch)();
 132
 133         if (af >= AF_MAX)
 134                 return (0);
 135         maybe = 0;
 136         netmatch = afswitch[af].af_netmatch;
 137         for (ifp = ifnet; ifp; ifp = ifp->int_next) {
 138                 if (ifp->int_addr.sa_family != af)
 139                         continue;
 140                 if (same(&ifp->int_addr, addr))
 141                         break;
 142                 if ((ifp->int_flags & IFF_BROADCAST) &&
 143                     same(&ifp->int_broadaddr, addr))
 144                         break;
 145                 if (maybe == 0 && (*netmatch)(addr, &ifp->int_addr))
 146                         maybe = ifp;
 147         }
 148         if (ifp == 0)
 149                 ifp = maybe;
 150         return (ifp);
 151 }