sysdeps/mach/hurd/if_index.c

   1 /* Find network interface names and index numbers.  Hurd version.
   2    Copyright (C) 2000-2015 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 weak_alias (__if_nametoindex, if_nametoindex)
  54 libc_hidden_weak (if_nametoindex)
  55
  56 /* Free the structure IFN returned by if_nameindex.  */
  57 void
  58 __if_freenameindex (struct if_nameindex *ifn)
  59 {
  60   struct if_nameindex *ptr = ifn;
  61   while (ptr->if_name || ptr->if_index)
  62     {
  63       free (ptr->if_name);
  64       ++ptr;
  65     }
  66   free (ifn);
  67 }
  68 weak_alias (__if_freenameindex, if_freenameindex)
  69
  70 /* Return an array of if_nameindex structures, one for each network
  71    interface present, plus one indicating the end of the array.  On
  72    error, return NULL.  */
  73 struct if_nameindex *
  74 __if_nameindex (void)
  75 {
  76   error_t err = 0;
  77   char data[2048];
  78   file_t server;
  79   int fd = __opensock ();
  80   struct ifconf ifc;
  81   unsigned int nifs, i;
  82   struct if_nameindex *idx = NULL;
  83
  84   ifc.ifc_buf = data;
  85
  86   if (fd < 0)
  87     return NULL;
  88
  89   server = _hurd_socket_server (PF_INET, 0);
  90   if (server == MACH_PORT_NULL)
  91     nifs = 0;
  92   else
  93     {
  94       size_t len = sizeof data;
  95       err = __pfinet_siocgifconf (server, -1, &ifc.ifc_buf, &len);
  96       if (err == MACH_SEND_INVALID_DEST || err == MIG_SERVER_DIED)
  97         {
  98           /* On the first use of the socket server during the operation,
  99              allow for the old server port dying.  */
 100           server = _hurd_socket_server (PF_INET, 1);
 101           if (server == MACH_PORT_NULL)
 102             goto out;
 103           err = __pfinet_siocgifconf (server, -1, &ifc.ifc_buf, &len);
 104         }
 105       if (err)
 106         goto out;
 107
 108       ifc.ifc_len = len;
 109       nifs = len / sizeof (struct ifreq);
 110     }
 111
 112   idx = malloc ((nifs + 1) * sizeof (struct if_nameindex));
 113   if (idx == NULL)
 114     {
 115       err = ENOBUFS;
 116       goto out;
 117     }
 118
 119   for (i = 0; i < nifs; ++i)
 120     {
 121       struct ifreq *ifr = &ifc.ifc_req[i];
 122       idx[i].if_name = __strdup (ifr->ifr_name);
 123       if (idx[i].if_name == NULL
 124           || __ioctl (fd, SIOCGIFINDEX, ifr) < 0)
 125         {
 126           unsigned int j;
 127           err = errno;
 128
 129           for (j =  0; j < i; ++j)
 130             free (idx[j].if_name);
 131           free (idx);
 132           idx = NULL;
 133
 134           if (err == EINVAL)
 135             err = ENOSYS;
 136           else if (err == ENOMEM)
 137             err = ENOBUFS;
 138           goto out;
 139         }
 140       idx[i].if_index = ifr->ifr_ifindex;
 141     }
 142
 143   idx[i].if_index = 0;
 144   idx[i].if_name = NULL;
 145
 146  out:
 147   __close (fd);
 148   if (data != ifc.ifc_buf)
 149     __vm_deallocate (__mach_task_self (), (vm_address_t) ifc.ifc_buf,
 150                      ifc.ifc_len);
 151   __set_errno (err);
 152   return idx;
 153 }
 154 weak_alias (__if_nameindex, if_nameindex)
 155
 156 /* Store the name of the interface corresponding to index IFINDEX in
 157    IFNAME (which has space for at least IFNAMSIZ characters).  Return
 158    IFNAME, or NULL on error.  */
 159 char *
 160 __if_indextoname (unsigned int ifindex, char *ifname)
 161 {
 162   struct ifreq ifr;
 163   int fd = __opensock ();
 164
 165   if (fd < 0)
 166     return NULL;
 167
 168   ifr.ifr_ifindex = ifindex;
 169   if (__ioctl (fd, SIOCGIFNAME, &ifr) < 0)
 170     {
 171       int saved_errno = errno;
 172       __close (fd);
 173       if (saved_errno == EINVAL || saved_errno == ENOTTY)
 174         __set_errno (ENOSYS);
 175       else if (saved_errno == ENODEV)
 176         __set_errno (ENXIO);
 177       return NULL;
 178     }
 179   __close (fd);
 180   return strncpy (ifname, ifr.ifr_name, IFNAMSIZ);
 181 }
 182 weak_alias (__if_indextoname, if_indextoname)
 183 libc_hidden_weak (if_indextoname)
 184
 185 #if 0
 186 void
 187 internal_function
 188 __protocol_available (int *have_inet, int *have_inet6)
 189 {
 190   *have_inet = _hurd_socket_server (PF_INET, 0) != MACH_PORT_NULL;
 191   *have_inet6 = _hurd_socket_server (PF_INET6, 0) != MACH_PORT_NULL;
 192 }
 193 #endif