nss/digits_dots.c

   1 /* Copyright (C) 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by H.J. Lu <hjl@gnu.ai.mit.edu>, 1997.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    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    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20   /*
  21    * disallow names consisting only of digits/dots, unless
  22    * they end in a dot.
  23    */
  24   if (isdigit (name[0]) || (isxdigit (name[0]) || name[0] == ':'))
  25     {
  26       const char *cp;
  27       char *hostname;
  28       typedef unsigned char host_addr_t [16];
  29       host_addr_t *host_addr;
  30       typedef char *host_addr_list_t [2];
  31       host_addr_list_t *host_aliases;
  32       host_addr_list_t *h_addr_ptrs;
  33       size_t size_needed;
  34       int addr_size;
  35 #ifndef HAVE_AF
  36       int af = -1;
  37 #endif
  38
  39       switch (af)
  40         {
  41         case AF_INET:
  42           addr_size = INADDRSZ;
  43           break;
  44
  45         case AF_INET6:
  46           addr_size = IN6ADDRSZ;
  47           break;
  48
  49         default:
  50           af = (_res.options & RES_USE_INET6) ? AF_INET6 : AF_INET;
  51           addr_size = (af == AF_INET6 ) ? IN6ADDRSZ : INADDRSZ;
  52           break;
  53         }
  54
  55       size_needed = (sizeof (*host_addr)
  56                      + sizeof (*host_aliases) + sizeof (*h_addr_ptrs)
  57                      + strlen (name) + 1);
  58
  59 #ifdef HAVE_LOOKUP_BUFFER
  60       if (buflen < size_needed)
  61         {
  62           __set_errno (ERANGE);
  63           goto done;
  64         }
  65 #else
  66       if (buffer_size < size_needed)
  67         {
  68           char *new_buf;
  69           buffer_size = size_needed;
  70           new_buf = realloc (buffer, buffer_size);
  71
  72           if (new_buf == NULL)
  73             {
  74               save = errno;
  75               free (buffer);
  76               buffer = NULL;
  77               buffer_size = 0;
  78               __set_errno (save);
  79               result = (struct hostent *) NULL;
  80               goto done;
  81             }
  82           buffer = new_buf;
  83         }
  84 #endif /* HAVE_LOOKUP_BUFFER */
  85
  86       memset (buffer, 0, size_needed);
  87
  88       host_addr = (host_addr_t *) buffer;
  89       host_aliases = (host_addr_list_t *)
  90         ((char *) host_addr + sizeof (*host_addr));
  91       h_addr_ptrs = (host_addr_list_t *)
  92         ((char *) host_aliases + sizeof (*host_aliases));
  93       hostname = (char *) h_addr_ptrs + sizeof (*h_addr_ptrs);
  94
  95       if (isdigit (name[0]))
  96         {
  97           for (cp = name;; ++cp)
  98             {
  99               if (!*cp)
 100                 {
 101                   if (*--cp == '.') break;
 102
 103         /* All-numeric, no dot at the end. Fake up a hostent as if
 104            we'd actually done a lookup.  What if someone types
 105            255.255.255.255?  The test below will succeed
 106            spuriously... ???  */
 107                   if (inet_pton (af, name, host_addr) <= 0)
 108                     {
 109                       __set_h_errno (HOST_NOT_FOUND);
 110 #ifndef HAVE_LOOKUP_BUFFER
 111                       result = (struct hostent *) NULL;
 112 #endif
 113                       goto done;
 114                     }
 115
 116                   resbuf.h_name = strcpy (hostname, name);
 117                   resbuf.h_aliases = *host_aliases;
 118                   (*host_aliases)[0] = NULL;
 119                   (*h_addr_ptrs)[0] = (char *)host_addr;
 120                   (*h_addr_ptrs)[1] = (char *)0;
 121                   resbuf.h_addr_list = *h_addr_ptrs;
 122                   if (_res.options & RES_USE_INET6 && af == AF_INET)
 123                     {
 124                       /* We need to change the IP v4 address into the
 125                          IP v6 address.  */
 126                       char tmp[INADDRSZ], *p = (char *) host_addr;
 127                       int i;
 128
 129                       /* Save a copy of the IP v4 address. */
 130                       memcpy (tmp, host_addr, INADDRSZ);
 131                       /* Mark this ipv6 addr as a mapped ipv4. */
 132                       for (i = 0; i < 10; i++)
 133                         *p++ = 0x00;
 134                       *p++ = 0xff;
 135                       *p++ = 0xff;
 136                       /* Copy the IP v4 address. */
 137                       memcpy (p, tmp, INADDRSZ);
 138                       resbuf.h_addrtype = AF_INET6;
 139                       resbuf.h_length = IN6ADDRSZ;
 140                     }
 141                   else
 142                     {
 143                       resbuf.h_addrtype = af;
 144                       resbuf.h_length = addr_size;
 145                     }
 146                   __set_h_errno (NETDB_SUCCESS);
 147 #ifdef HAVE_LOOKUP_BUFFER
 148                   status = NSS_STATUS_SUCCESS;
 149 #else
 150                   result = &resbuf;
 151 #endif
 152                   goto done;
 153                 }
 154
 155               if (!isdigit (*cp) && *cp != '.') break;
 156             }
 157         }
 158
 159       if ((isxdigit (name[0]) && strchr (name, ':') != NULL)
 160           || name[0] == ':')
 161         {
 162           const char *cp;
 163           char *hostname;
 164           typedef unsigned char host_addr_t [16];
 165           host_addr_t *host_addr;
 166           typedef char *host_addr_list_t [2];
 167           host_addr_list_t *host_aliases;
 168           host_addr_list_t *h_addr_ptrs;
 169           size_t size_needed;
 170           int addr_size;
 171 #ifndef HAVE_AF
 172           int af = -1;
 173 #endif
 174
 175           switch (af)
 176             {
 177             case AF_INET:
 178               addr_size = INADDRSZ;
 179               break;
 180
 181             case AF_INET6:
 182               addr_size = IN6ADDRSZ;
 183               break;
 184
 185             default:
 186               af = (_res.options & RES_USE_INET6) ? AF_INET6 : AF_INET;
 187               addr_size = (af == AF_INET6 ) ? IN6ADDRSZ : INADDRSZ;
 188               break;
 189             }
 190
 191           size_needed = (sizeof (*host_addr)
 192                          + sizeof (*host_aliases) + sizeof (*h_addr_ptrs)
 193                          + strlen (name) + 1);
 194
 195 #ifdef HAVE_LOOKUP_BUFFER
 196           if (buflen < size_needed)
 197             {
 198               __set_errno (ERANGE);
 199               goto done;
 200             }
 201 #else
 202           if (buffer_size < size_needed)
 203             {
 204               char *new_buf;
 205               buffer_size = size_needed;
 206               new_buf = realloc (buffer, buffer_size);
 207
 208               if (new_buf == NULL)
 209                 {
 210                   save = errno;
 211                   free (buffer);
 212                   __set_errno (save);
 213                   buffer = NULL;
 214                   buffer_size = 0;
 215                   result = (struct hostent *) NULL;
 216                   goto done;
 217                 }
 218               buffer = new_buf;
 219             }
 220 #endif /* HAVE_LOOKUP_BUFFER */
 221
 222           memset (buffer, 0, size_needed);
 223
 224           host_addr = (host_addr_t *) buffer;
 225           host_aliases = (host_addr_list_t *)
 226             ((char *) host_addr + sizeof (*host_addr));
 227           h_addr_ptrs = (host_addr_list_t *)
 228             ((char *) host_aliases + sizeof (*host_aliases));
 229           hostname = (char *) h_addr_ptrs + sizeof (*h_addr_ptrs);
 230
 231           for (cp = name;; ++cp)
 232             {
 233               if (!*cp)
 234                 {
 235                   if (*--cp == '.')
 236                     break;
 237
 238                   /* All-IPv6-legal, no dot at the end. Fake up a
 239                      hostent as if we'd actually done a lookup.  */
 240                   if (inet_pton (af, name, host_addr) <= 0)
 241                     {
 242                       __set_h_errno (HOST_NOT_FOUND);
 243 #ifndef HAVE_LOOKUP_BUFFER
 244                       result = (struct hostent *) NULL;
 245 #endif
 246                       goto done;
 247                     }
 248
 249                   strcpy (hostname, name);
 250                   resbuf.h_name = hostname;
 251                   resbuf.h_aliases = *host_aliases;
 252                   (*host_aliases)[0] = NULL;
 253                   (*h_addr_ptrs)[0] = (char *) host_addr;
 254                   (*h_addr_ptrs)[1] = (char *) 0;
 255                   resbuf.h_addr_list = *h_addr_ptrs;
 256                   resbuf.h_addrtype = af;
 257                   resbuf.h_length = addr_size;
 258                   __set_h_errno (NETDB_SUCCESS);
 259 #ifdef HAVE_LOOKUP_BUFFER
 260                   status = NSS_STATUS_SUCCESS;
 261 #else
 262                   result = &resbuf;
 263 #endif
 264                   goto done;
 265                 }
 266
 267               if (!isxdigit (*cp) && *cp != ':' && *cp != '.') break;
 268             }
 269         }
 270     }