1 /* $KAME: if_nametoindex.c,v 1.6 2000/11/24 08:18:54 itojun Exp $ */
4 * Copyright (c) 1997, 2000
5 * Berkeley Software Design, Inc. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
13 * THIS SOFTWARE IS PROVIDED BY Berkeley Software Design, Inc. ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL Berkeley Software Design, Inc. BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * BSDI Id: if_nametoindex.c,v 2.3 2000/04/17 22:38:05 dab Exp
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
31 #include "namespace.h"
32 #include <sys/types.h>
33 #include <sys/socket.h>
34 #include <sys/sockio.h>
36 #include <net/if_dl.h>
42 #include "un-namespace.h"
50 * The first function maps an interface name into its corresponding
55 * unsigned int if_nametoindex(const char *ifname);
57 * If the specified interface name does not exist, the return value is
58 * 0, and errno is set to ENXIO. If there was a system error (such as
59 * running out of memory), the return value is 0 and errno is set to the
60 * proper value (e.g., ENOMEM).
64 if_nametoindex(const char *ifname)
68 struct ifaddrs *ifaddrs, *ifa;
71 s = _socket(AF_INET, SOCK_DGRAM, 0);
73 strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
74 if (_ioctl(s, SIOCGIFINDEX, &ifr) != -1) {
76 return (ifr.ifr_index);
81 if (getifaddrs(&ifaddrs) < 0)
86 for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) {
88 ifa->ifa_addr->sa_family == AF_LINK &&
89 strcmp(ifa->ifa_name, ifname) == 0) {
90 ni = ((struct sockaddr_dl*)ifa->ifa_addr)->sdl_index;