| 1 | /* |
| 2 | * Copyright (c) 1983 The Regents of the University of California. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms are permitted |
| 6 | * provided that the above copyright notice and this paragraph are |
| 7 | * duplicated in all such forms and that any documentation, |
| 8 | * advertising materials, and other materials related to such |
| 9 | * distribution and use acknowledge that the software was developed |
| 10 | * by the University of California, Berkeley. The name of the |
| 11 | * University may not be used to endorse or promote products derived |
| 12 | * from this software without specific prior written permission. |
| 13 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR |
| 14 | * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED |
| 15 | * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| 16 | * |
| 17 | * static char sccsid[] = "@(#)if.c 5.1 (Berkeley) 6/4/85"; (routed/if.c) |
| 18 | */ |
| 19 | |
| 20 | #ifndef lint |
| 21 | static char sccsid[] = "@(#)if.c 5.1 (Berkeley) %G%"; |
| 22 | #endif /* not lint */ |
| 23 | |
| 24 | /* |
| 25 | * Routing Table Management Daemon |
| 26 | */ |
| 27 | #include "defs.h" |
| 28 | |
| 29 | extern struct interface *ifnet; |
| 30 | |
| 31 | /* |
| 32 | * Find the interface with address addr. |
| 33 | */ |
| 34 | struct interface * |
| 35 | if_ifwithaddr(addr) |
| 36 | struct sockaddr *addr; |
| 37 | { |
| 38 | register struct interface *ifp; |
| 39 | |
| 40 | #define same(a1, a2) \ |
| 41 | (bcmp((caddr_t)((a1)->sa_data), (caddr_t)((a2)->sa_data), 14) == 0) |
| 42 | for (ifp = ifnet; ifp; ifp = ifp->int_next) { |
| 43 | if (ifp->int_flags & IFF_REMOTE) |
| 44 | continue; |
| 45 | if (ifp->int_addr.sa_family != addr->sa_family) |
| 46 | continue; |
| 47 | if (same(&ifp->int_addr, addr)) |
| 48 | break; |
| 49 | if ((ifp->int_flags & IFF_BROADCAST) && |
| 50 | same(&ifp->int_broadaddr, addr)) |
| 51 | break; |
| 52 | } |
| 53 | return (ifp); |
| 54 | } |
| 55 | |
| 56 | /* |
| 57 | * Find the point-to-point interface with destination address addr. |
| 58 | */ |
| 59 | struct interface * |
| 60 | if_ifwithdstaddr(addr) |
| 61 | struct sockaddr *addr; |
| 62 | { |
| 63 | register struct interface *ifp; |
| 64 | |
| 65 | for (ifp = ifnet; ifp; ifp = ifp->int_next) { |
| 66 | if ((ifp->int_flags & IFF_POINTOPOINT) == 0) |
| 67 | continue; |
| 68 | if (same(&ifp->int_dstaddr, addr)) |
| 69 | break; |
| 70 | } |
| 71 | return (ifp); |
| 72 | } |
| 73 | |
| 74 | /* |
| 75 | * Find the interface on the network |
| 76 | * of the specified address. |
| 77 | */ |
| 78 | struct interface * |
| 79 | if_ifwithnet(addr) |
| 80 | register struct sockaddr *addr; |
| 81 | { |
| 82 | register struct interface *ifp; |
| 83 | register int af = addr->sa_family; |
| 84 | register int (*netmatch)(); |
| 85 | |
| 86 | if (af >= AF_MAX) |
| 87 | return (0); |
| 88 | netmatch = afswitch[af].af_netmatch; |
| 89 | for (ifp = ifnet; ifp; ifp = ifp->int_next) { |
| 90 | if (ifp->int_flags & IFF_REMOTE) |
| 91 | continue; |
| 92 | if (af != ifp->int_addr.sa_family) |
| 93 | continue; |
| 94 | if ((*netmatch)(addr, &ifp->int_addr)) |
| 95 | break; |
| 96 | } |
| 97 | return (ifp); |
| 98 | } |
| 99 | |
| 100 | /* |
| 101 | * Find an interface from which the specified address |
| 102 | * should have come from. Used for figuring out which |
| 103 | * interface a packet came in on -- for tracing. |
| 104 | */ |
| 105 | struct interface * |
| 106 | if_iflookup(addr) |
| 107 | struct sockaddr *addr; |
| 108 | { |
| 109 | register struct interface *ifp, *maybe; |
| 110 | register int af = addr->sa_family; |
| 111 | register int (*netmatch)(); |
| 112 | |
| 113 | if (af >= AF_MAX) |
| 114 | return (0); |
| 115 | maybe = 0; |
| 116 | netmatch = afswitch[af].af_netmatch; |
| 117 | for (ifp = ifnet; ifp; ifp = ifp->int_next) { |
| 118 | if (ifp->int_addr.sa_family != af) |
| 119 | continue; |
| 120 | if (same(&ifp->int_addr, addr)) |
| 121 | break; |
| 122 | if ((ifp->int_flags & IFF_BROADCAST) && |
| 123 | same(&ifp->int_broadaddr, addr)) |
| 124 | break; |
| 125 | if (maybe == 0 && (*netmatch)(addr, &ifp->int_addr)) |
| 126 | maybe = ifp; |
| 127 | } |
| 128 | if (ifp == 0) |
| 129 | ifp = maybe; |
| 130 | return (ifp); |
| 131 | } |