nis/nss_nisplus/nisplus-hosts.c

   1 /* Copyright (C) 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 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 #include <nss.h>
  21 #include <netdb.h>
  22 #include <errno.h>
  23 #include <ctype.h>
  24 #include <string.h>
  25 #include <netinet/in.h>
  26 #include <arpa/inet.h>
  27 #include <bits/libc-lock.h>
  28 #include <rpcsvc/nis.h>
  29
  30 #include "nss-nisplus.h"
  31
  32 __libc_lock_define_initialized (static, lock)
  33
  34 static nis_result *result = NULL;
  35 static nis_name tablename_val = NULL;
  36 static u_long tablename_len = 0;
  37
  38 #define NISENTRYVAL(idx,col,res) \
  39         ((res)->objects.objects_val[(idx)].EN_data.en_cols.en_cols_val[(col)].ec_value.ec_value_val)
  40
  41 #define NISENTRYLEN(idx,col,res) \
  42         ((res)->objects.objects_val[(idx)].EN_data.en_cols.en_cols_val[(col)].ec_value.ec_value_len)
  43
  44 /* Get implementation for some internal functions. */
  45 #include "../../resolv/mapv4v6addr.h"
  46
  47 static int
  48 _nss_nisplus_parse_hostent (nis_result *result, int af, struct hostent *host,
  49                             char *buffer, size_t buflen)
  50 {
  51   unsigned int i;
  52   char *first_unused = buffer;
  53   size_t room_left = buflen;
  54   char *data, *p, *line;
  55
  56   if (result == NULL)
  57     return 0;
  58
  59   if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS) ||
  60       __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ ||
  61       strcmp(result->objects.objects_val[0].EN_data.en_type,
  62              "hosts_tbl") != 0 ||
  63       result->objects.objects_val[0].EN_data.en_cols.en_cols_len < 4)
  64     return 0;
  65
  66   if (room_left < NISENTRYLEN (0, 2, result) + 1)
  67     {
  68     no_more_room:
  69       __set_errno (ERANGE);
  70       return -1;
  71     }
  72
  73   data = first_unused;
  74   if (inet_pton (af, NISENTRYVAL (0, 2, result), data) < 1)
  75     /* Illegal address: ignore line.  */
  76     return 0;
  77
  78   host->h_addrtype = af;
  79   if (af == AF_INET6)
  80     host->h_length = IN6ADDRSZ;
  81   else
  82     {
  83       if (_res.options & RES_USE_INET6)
  84         {
  85           map_v4v6_address (data, data);
  86           host->h_addrtype = AF_INET6;
  87           host->h_length = IN6ADDRSZ;
  88         }
  89       else
  90         {
  91           host->h_addrtype = AF_INET;
  92           host->h_length = INADDRSZ;
  93         }
  94     }
  95   first_unused+=host->h_length;
  96   room_left-=host->h_length;
  97
  98   if (NISENTRYLEN (0, 0, result) + 1 > room_left)
  99     goto no_more_room;
 100
 101   p = __stpncpy (first_unused, NISENTRYVAL (0, 0, result),
 102                  NISENTRYLEN (0, 0, result));
 103   *p = '\0';
 104   room_left -= (NISENTRYLEN (0, 0, result) + 1);
 105   host->h_name = first_unused;
 106   first_unused += NISENTRYLEN (0, 0, result) +1;
 107   p = first_unused;
 108
 109   line = p;
 110   for (i = 0; i < result->objects.objects_len; i++)
 111     {
 112       if (strcmp (NISENTRYVAL (i, 1, result), host->h_name) != 0)
 113         {
 114           if (NISENTRYLEN (i, 1, result) + 2 > room_left)
 115             goto no_more_room;
 116
 117           *p++ = ' ';
 118           p = __stpncpy (p, NISENTRYVAL (i, 1, result),
 119                          NISENTRYLEN (i, 1, result));
 120           *p = '\0';
 121           room_left -= (NISENTRYLEN (i, 1, result) + 1);
 122         }
 123     }
 124   ++p;
 125   first_unused = p;
 126   /* Adjust the pointer so it is aligned for
 127      storing pointers.  */
 128   first_unused += __alignof__ (char *) - 1;
 129   first_unused -= ((first_unused - (char *) 0) % __alignof__ (char *));
 130   host->h_addr_list = (char **) first_unused;
 131   if (room_left < 2 * sizeof (char *))
 132     goto no_more_room;
 133
 134   room_left -= (2 * sizeof (char *));
 135   host->h_addr_list[0] = data;
 136   host->h_addr_list[1] = NULL;
 137   host->h_aliases = &host->h_addr_list[2];
 138   host->h_aliases[0] = NULL;
 139
 140   i = 0;
 141   while (*line != '\0')
 142     {
 143       /* Skip leading blanks.  */
 144       while (isspace (*line))
 145         line++;
 146
 147       if (*line == '\0')
 148         break;
 149
 150       if (room_left < sizeof (char *))
 151         goto no_more_room;
 152
 153       room_left -= sizeof (char *);
 154       host->h_aliases[i] = line;
 155
 156       while (*line != '\0' && *line != ' ')
 157         ++line;
 158
 159       if (*line == ' ')
 160         {
 161           *line = '\0';
 162           ++line;
 163           ++i;
 164         }
 165       else
 166         host->h_aliases[i+1] = NULL;
 167     }
 168   return 1;
 169 }
 170
 171 static enum nss_status
 172 _nss_create_tablename (void)
 173 {
 174   if (tablename_val == NULL)
 175     {
 176       char buf [40 + strlen (nis_local_directory ())];
 177       char *p;
 178
 179       p = __stpcpy (buf, "hosts.org_dir.");
 180       p = __stpcpy (p, nis_local_directory ());
 181       tablename_val = __strdup (buf);
 182       if (tablename_val == NULL)
 183         return NSS_STATUS_TRYAGAIN;
 184       tablename_len = strlen (tablename_val);
 185     }
 186   return NSS_STATUS_SUCCESS;
 187 }
 188
 189 enum nss_status
 190 _nss_nisplus_sethostent (void)
 191 {
 192   enum nss_status status = NSS_STATUS_SUCCESS;
 193
 194   __libc_lock_lock (lock);
 195
 196   if (result)
 197     nis_freeresult (result);
 198   result = NULL;
 199
 200   if (tablename_val == NULL)
 201     if (_nss_create_tablename() != NSS_STATUS_SUCCESS)
 202       status = NSS_STATUS_UNAVAIL;
 203
 204   __libc_lock_unlock (lock);
 205
 206   return status;
 207 }
 208
 209 enum nss_status
 210 _nss_nisplus_endhostent (void)
 211 {
 212   __libc_lock_lock (lock);
 213
 214   if (result)
 215     nis_freeresult (result);
 216   result = NULL;
 217
 218   __libc_lock_unlock (lock);
 219
 220   return NSS_STATUS_SUCCESS;
 221 }
 222
 223 static enum nss_status
 224 internal_nisplus_gethostent_r (struct hostent *host, char *buffer,
 225                                size_t buflen, int *herrnop)
 226 {
 227   int parse_res;
 228
 229   /* Get the next entry until we found a correct one. */
 230   do
 231     {
 232       nis_result *saved_res;
 233
 234       if (result == NULL)
 235         {
 236           saved_res = NULL;
 237           if (tablename_val == NULL)
 238             if (_nss_create_tablename() != NSS_STATUS_SUCCESS)
 239               return NSS_STATUS_UNAVAIL;
 240
 241           result = nis_first_entry(tablename_val);
 242           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 243             {
 244               enum nss_status retval = niserr2nss (result->status);
 245               if (retval == NSS_STATUS_TRYAGAIN)
 246                 {
 247                   *herrnop = NETDB_INTERNAL;
 248                   __set_errno (EAGAIN);
 249                 }
 250               return retval;
 251             }
 252
 253         }
 254       else
 255         {
 256           nis_result *res2;
 257
 258           saved_res = result;
 259           res2 = nis_next_entry(tablename_val, &result->cookie);
 260           result = res2;
 261           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 262             {
 263               enum nss_status retval= niserr2nss (result->status);
 264
 265               nis_freeresult (result);
 266               result = saved_res;
 267               if (retval == NSS_STATUS_TRYAGAIN)
 268                 {
 269                   *herrnop = NETDB_INTERNAL;
 270                   __set_errno (EAGAIN);
 271                 }
 272               return retval;
 273             }
 274         }
 275
 276       parse_res = _nss_nisplus_parse_hostent (result, AF_INET6,
 277                                               host, buffer, buflen);
 278       if (parse_res < 1 && errno != ERANGE)
 279         parse_res = _nss_nisplus_parse_hostent (result, AF_INET, host,
 280                                                 buffer, buflen);
 281       if (parse_res < 1 && errno == ERANGE)
 282         {
 283           nis_freeresult (result);
 284           result = saved_res;
 285           *herrnop = NETDB_INTERNAL;
 286           return NSS_STATUS_TRYAGAIN;
 287         }
 288       if (saved_res != NULL)
 289         nis_freeresult (saved_res);
 290
 291     } while (!parse_res);
 292
 293   return NSS_STATUS_SUCCESS;
 294 }
 295
 296 enum nss_status
 297 _nss_nisplus_gethostent_r (struct hostent *result, char *buffer,
 298                            size_t buflen, int *herrnop)
 299 {
 300   int status;
 301
 302   __libc_lock_lock (lock);
 303
 304   status = internal_nisplus_gethostent_r (result, buffer, buflen, herrnop);
 305
 306   __libc_lock_unlock (lock);
 307
 308   return status;
 309 }
 310
 311 enum nss_status
 312 _nss_nisplus_gethostbyname2_r (const char *name, int af, struct hostent *host,
 313                               char *buffer, size_t buflen, int *herrnop)
 314 {
 315   int parse_res, retval;
 316
 317   if (tablename_val == NULL)
 318     if (_nss_create_tablename() != NSS_STATUS_SUCCESS)
 319       {
 320         *herrnop = NETDB_INTERNAL;
 321         return NSS_STATUS_UNAVAIL;
 322       }
 323
 324   if (name == NULL)
 325     {
 326       __set_errno (EINVAL);
 327       *herrnop = NETDB_INTERNAL;
 328       return NSS_STATUS_NOTFOUND;
 329     }
 330   else
 331     {
 332       nis_result *result;
 333       char buf[strlen (name) + 255 + tablename_len];
 334
 335       /* Search at first in the alias list, and use the correct name
 336          for the next search */
 337       sprintf(buf, "[name=%s],%s", name, tablename_val);
 338       result = nis_list(buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 339
 340       /* If we do not find it, try it as original name. But if the
 341          database is correct, we should find it in the first case, too */
 342       if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS) ||
 343           __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ ||
 344           strcmp(result->objects.objects_val->EN_data.en_type,
 345                  "hosts_tbl") != 0 ||
 346           result->objects.objects_val->EN_data.en_cols.en_cols_len < 3)
 347         sprintf(buf, "[cname=%s],%s", name, tablename_val);
 348       else
 349         sprintf(buf, "[cname=%s],%s", NISENTRYVAL(0, 0, result),
 350                 tablename_val);
 351
 352       nis_freeresult (result);
 353       result = nis_list(buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 354
 355       retval = niserr2nss (result->status);
 356       if (retval != NSS_STATUS_SUCCESS)
 357         {
 358           if (retval == NSS_STATUS_TRYAGAIN)
 359             {
 360               __set_errno (EAGAIN);
 361               *herrnop = NETDB_INTERNAL;
 362             }
 363           nis_freeresult (result);
 364           return retval;
 365         }
 366
 367       parse_res =
 368         _nss_nisplus_parse_hostent (result, af, host, buffer, buflen);
 369
 370       nis_freeresult (result);
 371
 372       if (parse_res > 0)
 373         return NSS_STATUS_SUCCESS;
 374
 375       *herrnop = NETDB_INTERNAL;
 376       if (parse_res == -1)
 377         return NSS_STATUS_TRYAGAIN;
 378       else
 379         return NSS_STATUS_NOTFOUND;
 380     }
 381 }
 382
 383 enum nss_status
 384 _nss_nisplus_gethostbyname_r (const char *name, struct hostent *host,
 385                               char *buffer, size_t buflen, int *h_errnop)
 386 {
 387   if (_res.options & RES_USE_INET6)
 388     {
 389       enum nss_status status;
 390
 391       status = _nss_nisplus_gethostbyname2_r (name, AF_INET6, host, buffer,
 392                                               buflen, h_errnop);
 393       if (status == NSS_STATUS_SUCCESS)
 394         return status;
 395     }
 396
 397   return _nss_nisplus_gethostbyname2_r (name, AF_INET, host, buffer,
 398                                         buflen, h_errnop);
 399 }
 400
 401 enum nss_status
 402 _nss_nisplus_gethostbyaddr_r (const char *addr, int addrlen, int type,
 403                               struct hostent *host, char *buffer,
 404                               size_t buflen, int *herrnop)
 405 {
 406   if (tablename_val == NULL)
 407     if (_nss_create_tablename() != NSS_STATUS_SUCCESS)
 408       return NSS_STATUS_UNAVAIL;
 409
 410   if (addr == NULL)
 411     return NSS_STATUS_NOTFOUND;
 412   else
 413     {
 414       nis_result *result;
 415       char buf[255 + tablename_len];
 416       int retval, parse_res;
 417
 418       sprintf (buf, "[addr=%s],%s",
 419                inet_ntoa (*(struct in_addr *)addr), tablename_val);
 420       result = nis_list(buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 421
 422       retval = niserr2nss (result->status);
 423       if (retval != NSS_STATUS_SUCCESS)
 424         {
 425           if (retval == NSS_STATUS_TRYAGAIN)
 426             {
 427               __set_errno (EAGAIN);
 428               *herrnop = NETDB_INTERNAL;
 429             }
 430           nis_freeresult (result);
 431           return retval;
 432         }
 433
 434       parse_res = _nss_nisplus_parse_hostent (result, type, host,
 435                                               buffer, buflen);
 436       nis_freeresult (result);
 437
 438       if (parse_res > 0)
 439         return NSS_STATUS_SUCCESS;
 440
 441       *herrnop = NETDB_INTERNAL;
 442       if (parse_res == -1)
 443         return NSS_STATUS_TRYAGAIN;
 444       else
 445         return NSS_STATUS_NOTFOUND;
 446     }
 447 }