mdw@git.distorted.org.uk Git - disorder/blob - lib/ifreq.c

   1 /*
   2  * This file is part of DisOrder.
   3  * Copyright (C) 2007 Richard Kettlewell
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  18  * USA
  19  */
  20 /** @file lib/ffreq.c
  21  * @brief Network interface support
  22  */
  23
  24 #include <config.h>
  25 #include "types.h"
  26
  27 #include <sys/socket.h>
  28 #include <sys/ioctl.h>
  29 #include <net/if.h>
  30 #include <netinet/in.h>
  31 #include <errno.h>
  32 #include <string.h>
  33
  34 #include "ifreq.h"
  35 #include "mem.h"
  36 #include "log.h"
  37
  38 /** @brief Get the list of network interfaces
  39  * @param fd File descriptor to use
  40  * @param interfaces Where to put pointer to array of interfaces
  41  * @param ninterfaces Where to put count of interfaces
  42  */
  43 void ifreq_list(int fd, struct ifreq **interfaces, int *ninterfaces) {
  44   struct ifconf ifc;
  45   int l;
  46
  47   ifc.ifc_len = 0;
  48   ifc.ifc_req = 0;
  49   do {
  50     l = ifc.ifc_len = ifc.ifc_len ? 2 * ifc.ifc_len
  51                                   : 16 * (int)sizeof (struct ifreq);
  52     if(!l) fatal(0, "out of memory");
  53     ifc.ifc_req = xrealloc(ifc.ifc_req, l);
  54     if(ioctl(fd, SIOCGIFCONF, &ifc) < 0)
  55       fatal(errno, "error calling ioctl SIOCGIFCONF");
  56   } while(l == ifc.ifc_len);
  57   *ninterfaces = ifc.ifc_len / sizeof (struct ifreq);
  58   *interfaces = ifc.ifc_req;
  59 }
  60
  61 /** @brief Return true if two socket addresses match */
  62 int sockaddr_equal(const struct sockaddr *a, const struct sockaddr *b) {
  63   if(a->sa_family != b->sa_family)
  64     return 0;
  65   switch(a->sa_family) {
  66   case AF_INET:
  67     return ((const struct sockaddr_in *)a)->sin_addr.s_addr
  68            == ((const struct sockaddr_in *)b)->sin_addr.s_addr;
  69   case AF_INET6:
  70     return !memcmp(&((const struct sockaddr_in6 *)a)->sin6_addr,
  71                    &((const struct sockaddr_in6 *)b)->sin6_addr,
  72                    sizeof (struct in6_addr));
  73   default:
  74     fatal(0, "unknown address family %d", a->sa_family);
  75   }
  76 }
  77
  78 /*
  79 Local Variables:
  80 c-basic-offset:2
  81 comment-column:40
  82 fill-column:79
  83 indent-tabs-mode:nil
  84 End:
  85 */