1 /* $OpenBSD: if_nametoindex.c,v 1.10 2015/10/23 13:09:19 claudio Exp $ */ 2 /* $KAME: if_nametoindex.c,v 1.5 2000/11/24 08:04:40 itojun Exp $ */ 3 4 /*- 5 * Copyright (c) 2015 Claudio Jeker <claudio@openbsd.org> 6 * Copyright (c) 1997, 2000 7 * Berkeley Software Design, Inc. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * THIS SOFTWARE IS PROVIDED BY Berkeley Software Design, Inc. ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL Berkeley Software Design, Inc. BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 * BSDI Id: if_nametoindex.c,v 2.3 2000/04/17 22:38:05 dab Exp 28 */ 29 30 #include <sys/types.h> 31 #include <sys/socket.h> 32 #include <net/if.h> 33 #include <stdlib.h> 34 #include <string.h> 35 #include <errno.h> 36 37 /* 38 * From RFC 2553: 39 * 40 * 4.1 Name-to-Index 41 * 42 * 43 * The first function maps an interface name into its corresponding 44 * index. 45 * 46 * #include <net/if.h> 47 * 48 * unsigned int if_nametoindex(const char *ifname); 49 * 50 * If the specified interface name does not exist, the return value is 51 * 0, and errno is set to ENXIO. If there was a system error (such as 52 * running out of memory), the return value is 0 and errno is set to the 53 * proper value (e.g., ENOMEM). 54 */ 55 56 unsigned int 57 if_nametoindex(const char *ifname) 58 { 59 struct if_nameindex *ifni, *ifni2; 60 unsigned int index; 61 62 if ((ifni = if_nameindex()) == NULL) 63 return(0); 64 65 for (ifni2 = ifni; ifni2->if_index != 0; ifni2++) { 66 if (strcmp(ifni2->if_name, ifname) == 0) { 67 index = ifni2->if_index; 68 if_freenameindex(ifni); 69 return index; 70 } 71 } 72 73 if_freenameindex(ifni); 74 errno = ENXIO; 75 return 0; 76 } 77 DEF_WEAK(if_nametoindex); 78