usr.sbin/traceroute/ifaddrlist.c

   1 /*      $NetBSD: ifaddrlist.c,v 1.10 2011/09/11 01:06:26 christos Exp $ */
   2
   3 /*
   4  * Copyright (c) 1997, 1998, 1999, 2000
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by the Computer Systems
  18  *      Engineering Group at Lawrence Berkeley Laboratory.
  19  * 4. Neither the name of the University nor of the Laboratory may be used
  20  *    to endorse or promote products derived from this software without
  21  *    specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include <sys/cdefs.h>
  37 #ifndef lint
  38 #if 0
  39 static const char rcsid[] =
  40     "@(#) Header: ifaddrlist.c,v 1.2 97/04/22 13:31:05 leres Exp  (LBL)";
  41     "@(#) Id: ifaddrlist.c,v 1.9 2000/11/23 20:01:55 leres Exp  (LBL)";
  42 #else
  43 __RCSID("$NetBSD: ifaddrlist.c,v 1.10 2011/09/11 01:06:26 christos Exp $");
  44 #endif
  45 #endif
  46
  47 #include <sys/param.h>
  48 #include <sys/file.h>
  49 #include <sys/ioctl.h>
  50 #include <sys/socket.h>
  51 #ifdef HAVE_SYS_SOCKIO_H
  52 #include <sys/sockio.h>
  53 #endif
  54 #include <sys/time.h>                           /* concession to AIX */
  55
  56 struct mbuf;
  57 struct rtentry;
  58
  59 #include <net/if.h>
  60 #include <netinet/in.h>
  61 #include <arpa/inet.h>
  62
  63 #include <ctype.h>
  64 #include <errno.h>
  65 #include <memory.h>
  66 #include <stdio.h>
  67 #include <stdlib.h>
  68 #include <string.h>
  69 #include <unistd.h>
  70 #include <ifaddrs.h>
  71
  72 #include "gnuc.h"
  73 #ifdef HAVE_OS_PROTO_H
  74 #include "os-proto.h"
  75 #endif
  76
  77 #include "ifaddrlist.h"
  78
  79 /* Not all systems have IFF_LOOPBACK */
  80 #ifdef IFF_LOOPBACK
  81 #define ISLOOPBACK(p) ((p)->ifa_flags & IFF_LOOPBACK)
  82 #else
  83 #define ISLOOPBACK(p) (strcmp((p)->ifa_name, "lo0") == 0)
  84 #endif
  85
  86 /*
  87  * Return the interface list
  88  */
  89 ssize_t
  90 ifaddrlist(struct ifaddrlist **ipaddrp, char *errbuf, size_t buflen)
  91 {
  92         struct sockaddr_in *sin;
  93         struct ifaddrs *ifap = NULL, *ifa;
  94         struct ifaddrlist *al = NULL, *nal;
  95         size_t i = 0, maxal = 10;
  96
  97         if (getifaddrs(&ifap) != 0)
  98                 goto out;
  99
 100         if ((al = malloc(maxal * sizeof(*al))) == NULL)
 101                 goto out;
 102
 103         for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
 104                 if (ifa->ifa_addr->sa_family != AF_INET)
 105                         continue;
 106
 107                 /* Must be up */
 108                 if ((ifa->ifa_flags & IFF_UP) == 0)
 109                         continue;
 110
 111                 /*
 112                  * Must not be a loopback address (127/8)
 113                  */
 114                 sin = (struct sockaddr_in *)ifa->ifa_addr;
 115                 if (ISLOOPBACK(ifa))
 116                         if (ntohl(sin->sin_addr.s_addr) == INADDR_LOOPBACK)
 117                                 continue;
 118
 119                 if (i == maxal) {
 120                         maxal <<= 1;
 121                         if ((nal = realloc(al, maxal * sizeof(*al))) == NULL)
 122                                 goto out;
 123                         al = nal;
 124                 }
 125
 126                 al[i].addr = sin->sin_addr.s_addr;
 127                 if ((al[i].device = strdup(ifa->ifa_name)) == NULL)
 128                         goto out;
 129                 i++;
 130         }
 131         if ((nal = realloc(al, i * sizeof(*al))) == NULL)
 132                 goto out;
 133         freeifaddrs(ifap);
 134         *ipaddrp = nal;
 135         return (ssize_t)i;
 136 out:
 137         if (ifap)
 138                 freeifaddrs(ifap);
 139         if (al) {
 140                 while (i > 0)
 141                         free(al[--i].device);
 142                 free(al);
 143         }
 144         (void)snprintf(errbuf, buflen, "%s: %s", __func__, strerror(errno));
 145         return -1;
 146 }