tests/net/if/ifconf.c

   1 /*      $NetBSD: ifconf.c,v 1.1 2014/12/08 04:23:03 ozaki-r Exp $       */
   2 /*
   3  * Copyright (c) 2014 The NetBSD Foundation, Inc.
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 #include <sys/cdefs.h>
  28 __RCSID("$NetBSD: ifconf.c,v 1.1 2014/12/08 04:23:03 ozaki-r Exp $");
  29 #include <sys/types.h>
  30 #include <sys/socket.h>
  31 #include <sys/sockio.h>
  32 #include <sys/ioctl.h>
  33
  34 #include <net/if.h>
  35
  36 #include <stdio.h>
  37 #include <err.h>
  38 #include <stdlib.h>
  39 #include <unistd.h>
  40 #include <string.h>
  41
  42 static void
  43 help(void)
  44 {
  45         fprintf(stderr, "usage:\n\t%s total\n\t%s list [<nifreqs>]\n",
  46             getprogname(), getprogname());
  47         exit(EXIT_FAILURE);
  48 }
  49
  50 static int
  51 get_number_of_entries(void)
  52 {
  53         int fd, r;
  54         struct ifconf ifc;
  55
  56         fd = socket(AF_INET, SOCK_DGRAM, 0);
  57         if (fd == -1)
  58                 err(EXIT_FAILURE, "socket");
  59
  60         ifc.ifc_len = 0;
  61         ifc.ifc_buf = NULL;
  62
  63         r = ioctl(fd, SIOCGIFCONF, &ifc);
  64         if (r == -1)
  65                 err(EXIT_FAILURE, "ioctl");
  66
  67         close(fd);
  68
  69         return ifc.ifc_len / sizeof(struct ifreq);
  70 }
  71
  72 static void
  73 show_number_of_entries(void)
  74 {
  75         printf("%d\n", get_number_of_entries());
  76 }
  77
  78 static void
  79 show_interfaces(int nifreqs)
  80 {
  81         int i, fd, r;
  82         struct ifconf ifc;
  83         struct ifreq *ifreqs;
  84
  85         if (nifreqs == 0)
  86                 nifreqs = get_number_of_entries();
  87
  88         if (nifreqs <= 0)
  89                 errx(EXIT_FAILURE, "nifreqs=%d", nifreqs);
  90
  91         ifreqs = malloc(sizeof(struct ifreq) * nifreqs);
  92         if (ifreqs == NULL)
  93                 err(EXIT_FAILURE, "malloc(sizeof(ifreq) * %d)", nifreqs);
  94
  95         fd = socket(AF_INET, SOCK_DGRAM, 0);
  96         if (fd == -1)
  97                 err(EXIT_FAILURE, "socket");
  98
  99         ifc.ifc_len = sizeof(struct ifreq) * nifreqs;
 100         ifc.ifc_req = ifreqs;
 101
 102         r = ioctl(fd, SIOCGIFCONF, &ifc);
 103         if (r == -1)
 104                 err(EXIT_FAILURE, "ioctl");
 105         close(fd);
 106
 107         for (i=0; i < (int)(ifc.ifc_len / sizeof(struct ifreq)); i++) {
 108                 printf("%s: af=%hhu socklen=%hhu\n", ifreqs[i].ifr_name,
 109                     ifreqs[i].ifr_addr.sa_family, ifreqs[i].ifr_addr.sa_len);
 110         }
 111
 112         free(ifreqs);
 113 }
 114
 115 int
 116 main(int argc, char *argv[])
 117 {
 118         if (argc < 2)
 119                 help();
 120
 121         if (strcmp(argv[1], "total") == 0) {
 122                 show_number_of_entries();
 123         } else if (strcmp(argv[1], "list") == 0) {
 124                 if (argc == 2)
 125                         show_interfaces(0);
 126                 else if (argc == 3)
 127                         show_interfaces(atoi(argv[2]));
 128                 else
 129                         help();
 130         } else
 131                 help();
 132
 133         return EXIT_SUCCESS;
 134 }