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
26 * $FreeBSD: src/lib/libc/net/if_nametoindex.c,v 1.5 2003/05/01 19:03:14 nectar Exp $
27 * $DragonFly: src/lib/libc/net/if_nametoindex.c,v 1.2 2003/06/17 04:26:44 dillon Exp $
30 #include "namespace.h"
31 #include <sys/types.h>
32 #include <sys/socket.h>
33 #include <sys/sockio.h>
35 #include <net/if_dl.h>
41 #include "un-namespace.h"
49 * The first function maps an interface name into its corresponding
54 * unsigned int if_nametoindex(const char *ifname);
56 * If the specified interface name does not exist, the return value is
57 * 0, and errno is set to ENXIO. If there was a system error (such as
58 * running out of memory), the return value is 0 and errno is set to the
59 * proper value (e.g., ENOMEM).
63 if_nametoindex(const char *ifname
)
67 struct ifaddrs
*ifaddrs
, *ifa
;
70 s
= _socket(AF_INET
, SOCK_DGRAM
, 0);
72 strlcpy(ifr
.ifr_name
, ifname
, sizeof(ifr
.ifr_name
));
73 if (_ioctl(s
, SIOCGIFINDEX
, &ifr
) != -1) {
75 return (ifr
.ifr_index
);
80 if (getifaddrs(&ifaddrs
) < 0)
85 for (ifa
= ifaddrs
; ifa
!= NULL
; ifa
= ifa
->ifa_next
) {
87 ifa
->ifa_addr
->sa_family
== AF_LINK
&&
88 strcmp(ifa
->ifa_name
, ifname
) == 0) {
89 ni
= ((struct sockaddr_dl
*)ifa
->ifa_addr
)->sdl_index
;