nis/nss_nisplus/nisplus-hosts.c

   1 /* Copyright (C) 1997, 1998 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, int *errnop)
  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       *errnop = 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++ = '\0';
 125   first_unused = p;
 126
 127   /* Adjust the pointer so it is aligned for
 128      storing pointers.  */
 129   first_unused += __alignof__ (char *) - 1;
 130   first_unused -= ((first_unused - (char *) 0) % __alignof__ (char *));
 131   host->h_addr_list = (char **) first_unused;
 132   if (room_left < 2 * sizeof (char *))
 133     goto no_more_room;
 134
 135   room_left -= (2 * sizeof (char *));
 136   host->h_addr_list[0] = data;
 137   host->h_addr_list[1] = NULL;
 138   host->h_aliases = &host->h_addr_list[2];
 139   host->h_aliases[0] = NULL;
 140
 141   i = 0;
 142   while (*line != '\0')
 143     {
 144       /* Skip leading blanks.  */
 145       while (isspace (*line))
 146         ++line;
 147
 148       if (*line == '\0')
 149         break;
 150
 151       if (room_left < sizeof (char *))
 152         goto no_more_room;
 153
 154       room_left -= sizeof (char *);
 155       host->h_aliases[i] = line;
 156
 157       while (*line != '\0' && *line != ' ')
 158         ++line;
 159
 160       if (*line == ' ')
 161         {
 162           *line = '\0';
 163           ++line;
 164           ++i;
 165         }
 166       else
 167         host->h_aliases[i+1] = NULL;
 168     }
 169   return 1;
 170 }
 171
 172 static enum nss_status
 173 _nss_create_tablename (int *errnop)
 174 {
 175   if (tablename_val == NULL)
 176     {
 177       char buf [40 + strlen (nis_local_directory ())];
 178       char *p;
 179
 180       p = __stpcpy (buf, "hosts.org_dir.");
 181       p = __stpcpy (p, nis_local_directory ());
 182       tablename_val = __strdup (buf);
 183       if (tablename_val == NULL)
 184         {
 185           *errnop = errno;
 186           return NSS_STATUS_TRYAGAIN;
 187         }
 188       tablename_len = strlen (tablename_val);
 189     }
 190   return NSS_STATUS_SUCCESS;
 191 }
 192
 193 enum nss_status
 194 _nss_nisplus_sethostent (void)
 195 {
 196   enum nss_status status = NSS_STATUS_SUCCESS;
 197   int err;
 198
 199   __libc_lock_lock (lock);
 200
 201   if (result)
 202     nis_freeresult (result);
 203   result = NULL;
 204
 205   if (tablename_val == NULL)
 206     status = _nss_create_tablename (&err);
 207
 208   __libc_lock_unlock (lock);
 209
 210   return status;
 211 }
 212
 213 enum nss_status
 214 _nss_nisplus_endhostent (void)
 215 {
 216   __libc_lock_lock (lock);
 217
 218   if (result)
 219     nis_freeresult (result);
 220   result = NULL;
 221
 222   __libc_lock_unlock (lock);
 223
 224   return NSS_STATUS_SUCCESS;
 225 }
 226
 227 static enum nss_status
 228 internal_nisplus_gethostent_r (struct hostent *host, char *buffer,
 229                                size_t buflen, int *errnop, int *herrnop)
 230 {
 231   int parse_res;
 232
 233   /* Get the next entry until we found a correct one. */
 234   do
 235     {
 236       nis_result *saved_res;
 237
 238       if (result == NULL)
 239         {
 240           saved_res = NULL;
 241           if (tablename_val == NULL)
 242             {
 243               enum nss_status status = _nss_create_tablename (errnop);
 244
 245               if (status != NSS_STATUS_SUCCESS)
 246                 return status;
 247             }
 248
 249           result = nis_first_entry (tablename_val);
 250           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 251             {
 252               enum nss_status retval = niserr2nss (result->status);
 253               if (retval == NSS_STATUS_TRYAGAIN)
 254                 {
 255                   *herrnop = NETDB_INTERNAL;
 256                   *errnop = errno;
 257                 }
 258               return retval;
 259             }
 260
 261         }
 262       else
 263         {
 264           nis_result *res2;
 265
 266           saved_res = result;
 267           res2 = nis_next_entry(tablename_val, &result->cookie);
 268           result = res2;
 269           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 270             {
 271               enum nss_status retval= niserr2nss (result->status);
 272
 273               nis_freeresult (result);
 274               result = saved_res;
 275               if (retval == NSS_STATUS_TRYAGAIN)
 276                 {
 277                   *herrnop = NETDB_INTERNAL;
 278                   *errnop = errno;
 279                 }
 280               return retval;
 281             }
 282         }
 283
 284       parse_res = _nss_nisplus_parse_hostent (result, AF_INET6, host, buffer,
 285                                               buflen, errnop);
 286       if (parse_res < 1 && *errnop != ERANGE)
 287         parse_res = _nss_nisplus_parse_hostent (result, AF_INET, host,
 288                                                 buffer, buflen, errnop);
 289       if (parse_res == -1)
 290         {
 291           nis_freeresult (result);
 292           result = saved_res;
 293           *herrnop = NETDB_INTERNAL;
 294           *errnop = ERANGE;
 295           return NSS_STATUS_TRYAGAIN;
 296         }
 297       if (saved_res != NULL)
 298         nis_freeresult (saved_res);
 299
 300     } while (!parse_res);
 301
 302   return NSS_STATUS_SUCCESS;
 303 }
 304
 305 enum nss_status
 306 _nss_nisplus_gethostent_r (struct hostent *result, char *buffer,
 307                            size_t buflen, int *errnop, int *herrnop)
 308 {
 309   int status;
 310
 311   __libc_lock_lock (lock);
 312
 313   status = internal_nisplus_gethostent_r (result, buffer, buflen, errnop,
 314                                           herrnop);
 315
 316   __libc_lock_unlock (lock);
 317
 318   return status;
 319 }
 320
 321 enum nss_status
 322 _nss_nisplus_gethostbyname2_r (const char *name, int af, struct hostent *host,
 323                                char *buffer, size_t buflen, int *errnop,
 324                                int *herrnop)
 325 {
 326   int parse_res, retval;
 327
 328   if (tablename_val == NULL)
 329     {
 330       enum nss_status status = _nss_create_tablename (errnop);
 331
 332       if (status != NSS_STATUS_SUCCESS)
 333         {
 334           *herrnop = NETDB_INTERNAL;
 335           return NSS_STATUS_UNAVAIL;
 336         }
 337     }
 338
 339   if (name == NULL)
 340     {
 341       *errnop = EINVAL;
 342       *herrnop = NETDB_INTERNAL;
 343       return NSS_STATUS_NOTFOUND;
 344     }
 345   else
 346     {
 347       nis_result *result;
 348       char buf[strlen (name) + 255 + tablename_len];
 349
 350       /* Search at first in the alias list, and use the correct name
 351          for the next search */
 352       sprintf (buf, "[name=%s],%s", name, tablename_val);
 353       result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 354
 355       /* If we do not find it, try it as original name. But if the
 356          database is correct, we should find it in the first case, too */
 357       if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS)
 358           || __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ
 359           || strcmp (result->objects.objects_val->EN_data.en_type,
 360                      "hosts_tbl") != 0
 361           || result->objects.objects_val->EN_data.en_cols.en_cols_len < 3)
 362         sprintf (buf, "[cname=%s],%s", name, tablename_val);
 363       else
 364         sprintf (buf, "[cname=%s],%s", NISENTRYVAL(0, 0, result),
 365                  tablename_val);
 366
 367       nis_freeresult (result);
 368       result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 369
 370       retval = niserr2nss (result->status);
 371       if (retval != NSS_STATUS_SUCCESS)
 372         {
 373           if (retval == NSS_STATUS_TRYAGAIN)
 374             {
 375               *errnop = errno;
 376               *herrnop = NETDB_INTERNAL;
 377             }
 378           nis_freeresult (result);
 379           return retval;
 380         }
 381
 382       parse_res = _nss_nisplus_parse_hostent (result, af, host, buffer,
 383                                               buflen, errnop);
 384
 385       nis_freeresult (result);
 386
 387       if (parse_res > 0)
 388         return NSS_STATUS_SUCCESS;
 389
 390       *herrnop = NETDB_INTERNAL;
 391       if (parse_res == -1)
 392         {
 393           *errnop = ERANGE;
 394           return NSS_STATUS_TRYAGAIN;
 395         }
 396       else
 397         return NSS_STATUS_NOTFOUND;
 398     }
 399 }
 400
 401 enum nss_status
 402 _nss_nisplus_gethostbyname_r (const char *name, struct hostent *host,
 403                               char *buffer, size_t buflen, int *errnop,
 404                               int *h_errnop)
 405 {
 406   if (_res.options & RES_USE_INET6)
 407     {
 408       enum nss_status status;
 409
 410       status = _nss_nisplus_gethostbyname2_r (name, AF_INET6, host, buffer,
 411                                               buflen, errnop, h_errnop);
 412       if (status == NSS_STATUS_SUCCESS)
 413         return status;
 414     }
 415
 416   return _nss_nisplus_gethostbyname2_r (name, AF_INET, host, buffer,
 417                                         buflen, errnop, h_errnop);
 418 }
 419
 420 enum nss_status
 421 _nss_nisplus_gethostbyaddr_r (const char *addr, int addrlen, int type,
 422                               struct hostent *host, char *buffer,
 423                               size_t buflen, int *errnop, int *herrnop)
 424 {
 425   if (tablename_val == NULL)
 426     {
 427       enum nss_status status = _nss_create_tablename (errnop);
 428
 429       if (status != NSS_STATUS_SUCCESS)
 430         return status;
 431     }
 432
 433   if (addr == NULL)
 434     return NSS_STATUS_NOTFOUND;
 435   else
 436     {
 437       nis_result *result;
 438       char buf[255 + tablename_len];
 439       int retval, parse_res;
 440
 441       sprintf (buf, "[addr=%s],%s",
 442                inet_ntoa (*(struct in_addr *) addr), tablename_val);
 443       result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 444
 445       retval = niserr2nss (result->status);
 446       if (retval != NSS_STATUS_SUCCESS)
 447         {
 448           if (retval == NSS_STATUS_TRYAGAIN)
 449             {
 450               *errnop = errno;
 451               *herrnop = NETDB_INTERNAL;
 452             }
 453           nis_freeresult (result);
 454           return retval;
 455         }
 456
 457       parse_res = _nss_nisplus_parse_hostent (result, type, host,
 458                                               buffer, buflen, errnop);
 459       nis_freeresult (result);
 460
 461       if (parse_res > 0)
 462         return NSS_STATUS_SUCCESS;
 463
 464       *herrnop = NETDB_INTERNAL;
 465       if (parse_res == -1)
 466         {
 467           *errnop = ERANGE;
 468           return NSS_STATUS_TRYAGAIN;
 469         }
 470       else
 471         return NSS_STATUS_NOTFOUND;
 472     }
 473 }