| 1 | /* |
| 2 | * Copyright (c) 1983 The Regents of the University of California. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * %sccs.include.redist.c% |
| 6 | * |
| 7 | * static char sccsid[] = "@(#)if.c 5.1 (Berkeley) 6/4/85"; (routed/if.c) |
| 8 | */ |
| 9 | |
| 10 | #ifndef lint |
| 11 | static char sccsid[] = "@(#)if.c 5.2 (Berkeley) %G%"; |
| 12 | #endif /* not lint */ |
| 13 | |
| 14 | /* |
| 15 | * Routing Table Management Daemon |
| 16 | */ |
| 17 | #include "defs.h" |
| 18 | |
| 19 | extern struct interface *ifnet; |
| 20 | |
| 21 | /* |
| 22 | * Find the interface with address addr. |
| 23 | */ |
| 24 | struct interface * |
| 25 | if_ifwithaddr(addr) |
| 26 | struct sockaddr *addr; |
| 27 | { |
| 28 | register struct interface *ifp; |
| 29 | |
| 30 | #define same(a1, a2) \ |
| 31 | (bcmp((caddr_t)((a1)->sa_data), (caddr_t)((a2)->sa_data), 14) == 0) |
| 32 | for (ifp = ifnet; ifp; ifp = ifp->int_next) { |
| 33 | if (ifp->int_flags & IFF_REMOTE) |
| 34 | continue; |
| 35 | if (ifp->int_addr.sa_family != addr->sa_family) |
| 36 | continue; |
| 37 | if (same(&ifp->int_addr, addr)) |
| 38 | break; |
| 39 | if ((ifp->int_flags & IFF_BROADCAST) && |
| 40 | same(&ifp->int_broadaddr, addr)) |
| 41 | break; |
| 42 | } |
| 43 | return (ifp); |
| 44 | } |
| 45 | |
| 46 | /* |
| 47 | * Find the point-to-point interface with destination address addr. |
| 48 | */ |
| 49 | struct interface * |
| 50 | if_ifwithdstaddr(addr) |
| 51 | struct sockaddr *addr; |
| 52 | { |
| 53 | register struct interface *ifp; |
| 54 | |
| 55 | for (ifp = ifnet; ifp; ifp = ifp->int_next) { |
| 56 | if ((ifp->int_flags & IFF_POINTOPOINT) == 0) |
| 57 | continue; |
| 58 | if (same(&ifp->int_dstaddr, addr)) |
| 59 | break; |
| 60 | } |
| 61 | return (ifp); |
| 62 | } |
| 63 | |
| 64 | /* |
| 65 | * Find the interface on the network |
| 66 | * of the specified address. |
| 67 | */ |
| 68 | struct interface * |
| 69 | if_ifwithnet(addr) |
| 70 | register struct sockaddr *addr; |
| 71 | { |
| 72 | register struct interface *ifp; |
| 73 | register int af = addr->sa_family; |
| 74 | register int (*netmatch)(); |
| 75 | |
| 76 | if (af >= AF_MAX) |
| 77 | return (0); |
| 78 | netmatch = afswitch[af].af_netmatch; |
| 79 | for (ifp = ifnet; ifp; ifp = ifp->int_next) { |
| 80 | if (ifp->int_flags & IFF_REMOTE) |
| 81 | continue; |
| 82 | if (af != ifp->int_addr.sa_family) |
| 83 | continue; |
| 84 | if ((*netmatch)(addr, &ifp->int_addr)) |
| 85 | break; |
| 86 | } |
| 87 | return (ifp); |
| 88 | } |
| 89 | |
| 90 | /* |
| 91 | * Find an interface from which the specified address |
| 92 | * should have come from. Used for figuring out which |
| 93 | * interface a packet came in on -- for tracing. |
| 94 | */ |
| 95 | struct interface * |
| 96 | if_iflookup(addr) |
| 97 | struct sockaddr *addr; |
| 98 | { |
| 99 | register struct interface *ifp, *maybe; |
| 100 | register int af = addr->sa_family; |
| 101 | register int (*netmatch)(); |
| 102 | |
| 103 | if (af >= AF_MAX) |
| 104 | return (0); |
| 105 | maybe = 0; |
| 106 | netmatch = afswitch[af].af_netmatch; |
| 107 | for (ifp = ifnet; ifp; ifp = ifp->int_next) { |
| 108 | if (ifp->int_addr.sa_family != af) |
| 109 | continue; |
| 110 | if (same(&ifp->int_addr, addr)) |
| 111 | break; |
| 112 | if ((ifp->int_flags & IFF_BROADCAST) && |
| 113 | same(&ifp->int_broadaddr, addr)) |
| 114 | break; |
| 115 | if (maybe == 0 && (*netmatch)(addr, &ifp->int_addr)) |
| 116 | maybe = ifp; |
| 117 | } |
| 118 | if (ifp == 0) |
| 119 | ifp = maybe; |
| 120 | return (ifp); |
| 121 | } |