sysdeps/mach/hurd/if_index.c

   1 /* Find network interface names and index numbers.  Hurd version.
   2    Copyright (C) 2000-2014 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <error.h>
  20 #include <net/if.h>
  21 #include <string.h>
  22 #include <sys/ioctl.h>
  23 #include <unistd.h>
  24
  25 #include <hurd.h>
  26 #include <hurd/ioctl.h>
  27 #include <hurd/pfinet.h>
  28
  29 /* Return the interface index corresponding to interface IFNAME.
  30    On error, return 0.  */
  31 unsigned int
  32 if_nametoindex (const char *ifname)
  33 {
  34   struct ifreq ifr;
  35   int fd = __opensock ();
  36
  37   if (fd < 0)
  38     return 0;
  39
  40   strncpy (ifr.ifr_name, ifname, IFNAMSIZ);
  41   if (__ioctl (fd, SIOCGIFINDEX, &ifr) < 0)
  42     {
  43       int saved_errno = errno;
  44       __close (fd);
  45       if (saved_errno == EINVAL || saved_errno == ENOTTY)
  46         __set_errno (ENOSYS);
  47       return 0;
  48     }
  49   __close (fd);
  50   return ifr.ifr_ifindex;
  51 }
  52 libc_hidden_def (if_nametoindex)
  53
  54 /* Free the structure IFN returned by if_nameindex.  */
  55 void
  56 if_freenameindex (struct if_nameindex *ifn)
  57 {
  58   struct if_nameindex *ptr = ifn;
  59   while (ptr->if_name || ptr->if_index)
  60     {
  61       free (ptr->if_name);
  62       ++ptr;
  63     }
  64   free (ifn);
  65 }
  66
  67 /* Return an array of if_nameindex structures, one for each network
  68    interface present, plus one indicating the end of the array.  On
  69    error, return NULL.  */
  70 struct if_nameindex *
  71 if_nameindex (void)
  72 {
  73   error_t err = 0;
  74   char data[2048];
  75   file_t server;
  76   int fd = __opensock ();
  77   struct ifconf ifc;
  78   unsigned int nifs, i;
  79   struct if_nameindex *idx = NULL;
  80
  81   ifc.ifc_buf = data;
  82
  83   if (fd < 0)
  84     return NULL;
  85
  86   server = _hurd_socket_server (PF_INET, 0);
  87   if (server == MACH_PORT_NULL)
  88     nifs = 0;
  89   else
  90     {
  91       size_t len = sizeof data;
  92       err = __pfinet_siocgifconf (server, -1, &ifc.ifc_buf, &len);
  93       if (err == MACH_SEND_INVALID_DEST || err == MIG_SERVER_DIED)
  94         {
  95           /* On the first use of the socket server during the operation,
  96              allow for the old server port dying.  */
  97           server = _hurd_socket_server (PF_INET, 1);
  98           if (server == MACH_PORT_NULL)
  99             goto out;
 100           err = __pfinet_siocgifconf (server, -1, &ifc.ifc_buf, &len);
 101         }
 102       if (err)
 103         goto out;
 104
 105       ifc.ifc_len = len;
 106       nifs = len / sizeof (struct ifreq);
 107     }
 108
 109   idx = malloc ((nifs + 1) * sizeof (struct if_nameindex));
 110   if (idx == NULL)
 111     {
 112       err = ENOBUFS;
 113       goto out;
 114     }
 115
 116   for (i = 0; i < nifs; ++i)
 117     {
 118       struct ifreq *ifr = &ifc.ifc_req[i];
 119       idx[i].if_name = __strdup (ifr->ifr_name);
 120       if (idx[i].if_name == NULL
 121           || __ioctl (fd, SIOCGIFINDEX, ifr) < 0)
 122         {
 123           unsigned int j;
 124           err = errno;
 125
 126           for (j =  0; j < i; ++j)
 127             free (idx[j].if_name);
 128           free (idx);
 129           idx = NULL;
 130
 131           if (err == EINVAL)
 132             err = ENOSYS;
 133           else if (err == ENOMEM)
 134             err = ENOBUFS;
 135           goto out;
 136         }
 137       idx[i].if_index = ifr->ifr_ifindex;
 138     }
 139
 140   idx[i].if_index = 0;
 141   idx[i].if_name = NULL;
 142
 143  out:
 144   __close (fd);
 145   if (data != ifc.ifc_buf)
 146     __vm_deallocate (__mach_task_self (), (vm_address_t) ifc.ifc_buf,
 147                      ifc.ifc_len);
 148   __set_errno (err);
 149   return idx;
 150 }
 151
 152 /* Store the name of the interface corresponding to index IFINDEX in
 153    IFNAME (which has space for at least IFNAMSIZ characters).  Return
 154    IFNAME, or NULL on error.  */
 155 char *
 156 if_indextoname (unsigned int ifindex, char *ifname)
 157 {
 158   struct ifreq ifr;
 159   int fd = __opensock ();
 160
 161   if (fd < 0)
 162     return NULL;
 163
 164   ifr.ifr_ifindex = ifindex;
 165   if (__ioctl (fd, SIOCGIFNAME, &ifr) < 0)
 166     {
 167       int saved_errno = errno;
 168       __close (fd);
 169       if (saved_errno == EINVAL || saved_errno == ENOTTY)
 170         __set_errno (ENOSYS);
 171       else if (saved_errno == ENODEV)
 172         __set_errno (ENXIO);
 173       return NULL;
 174     }
 175   __close (fd);
 176   return strncpy (ifname, ifr.ifr_name, IFNAMSIZ);
 177 }
 178 libc_hidden_def (if_indextoname)
 179
 180 #if 0
 181 void
 182 internal_function
 183 __protocol_available (int *have_inet, int *have_inet6)
 184 {
 185   *have_inet = _hurd_socket_server (PF_INET, 0) != MACH_PORT_NULL;
 186   *have_inet6 = _hurd_socket_server (PF_INET6, 0) != MACH_PORT_NULL;
 187 }
 188 #endif