nis/nss_nisplus/nisplus-network.c

   1 /* Copyright (C) 1997,1998,2000-2003,2005 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 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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <atomic.h>
  21 #include <ctype.h>
  22 #include <errno.h>
  23 #include <netdb.h>
  24 #include <nss.h>
  25 #include <stdint.h>
  26 #include <string.h>
  27 #include <arpa/inet.h>
  28 #include <rpcsvc/nis.h>
  29 #include <bits/libc-lock.h>
  30
  31 #include "nss-nisplus.h"
  32
  33 __libc_lock_define_initialized (static, lock)
  34
  35 static nis_result *result;
  36 static nis_name tablename_val;
  37 static u_long tablename_len;
  38
  39 #define NISENTRYVAL(idx,col,res) \
  40         ((res)->objects.objects_val[(idx)].EN_data.en_cols.en_cols_val[(col)].ec_value.ec_value_val)
  41
  42 #define NISENTRYLEN(idx,col,res) \
  43         ((res)->objects.objects_val[(idx)].EN_data.en_cols.en_cols_val[(col)].ec_value.ec_value_len)
  44
  45
  46 static int
  47 _nss_nisplus_parse_netent (nis_result *result, struct netent *network,
  48                            char *buffer, size_t buflen, int *errnop)
  49 {
  50   char *first_unused = buffer;
  51   size_t room_left = buflen;
  52
  53   if (result == NULL)
  54     return 0;
  55
  56   if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS)
  57       || __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ
  58       || strcmp (result->objects.objects_val[0].EN_data.en_type,
  59                  "networks_tbl") != 0
  60       || result->objects.objects_val[0].EN_data.en_cols.en_cols_len < 3)
  61     return 0;
  62
  63   if (NISENTRYLEN (0, 0, result) >= room_left)
  64     {
  65       /* The line is too long for our buffer.  */
  66     no_more_room:
  67       *errnop = ERANGE;
  68       return -1;
  69     }
  70
  71   strncpy (first_unused, NISENTRYVAL (0, 0, result),
  72            NISENTRYLEN (0, 0, result));
  73   first_unused[NISENTRYLEN (0, 0, result)] = '\0';
  74   network->n_name = first_unused;
  75   room_left -= (strlen (first_unused) +1);
  76   first_unused += strlen (first_unused) +1;
  77   network->n_addrtype = 0;
  78   network->n_net = inet_network (NISENTRYVAL (0, 2, result));
  79   char *p = first_unused;
  80
  81   char *line = p;
  82   for (unsigned int i = 0; i < result->objects.objects_len; ++i)
  83     {
  84       if (strcmp (NISENTRYVAL (i, 1, result), network->n_name) != 0)
  85         {
  86           if (NISENTRYLEN (i, 1, result) + 2 > room_left)
  87             goto no_more_room;
  88
  89           *p++ = ' ';
  90           p = __stpncpy (p, NISENTRYVAL (i, 1, result),
  91                          NISENTRYLEN (i, 1, result));
  92           *p = '\0';
  93           room_left -= (NISENTRYLEN (i, 1, result) + 1);
  94         }
  95     }
  96   *p++ = '\0';
  97   first_unused = p;
  98
  99   /* Adjust the pointer so it is aligned for
 100      storing pointers.  */
 101   first_unused += __alignof__ (char *) - 1;
 102   first_unused -= ((first_unused - (char *) 0) % __alignof__ (char *));
 103   network->n_aliases = (char **) first_unused;
 104   if (room_left < 2 * sizeof (char *))
 105     goto no_more_room;
 106   room_left -= (2 * sizeof (char *));
 107   network->n_aliases[0] = NULL;
 108
 109   unsigned int i = 0;
 110   while (*line != '\0')
 111     {
 112       /* Skip leading blanks.  */
 113       while (isspace (*line))
 114         ++line;
 115
 116       if (*line == '\0')
 117         break;
 118
 119       if (room_left < sizeof (char *))
 120         goto no_more_room;
 121
 122       room_left -= sizeof (char *);
 123       network->n_aliases[i] = line;
 124
 125       while (*line != '\0' && *line != ' ')
 126         ++line;
 127
 128       if (*line == ' ')
 129         {
 130           *line = '\0';
 131           ++line;
 132           ++i;
 133         }
 134       else
 135         network->n_aliases[i + 1] = NULL;
 136     }
 137
 138   return 1;
 139 }
 140
 141 static enum nss_status
 142 _nss_create_tablename (int *errnop)
 143 {
 144   if (tablename_val == NULL)
 145     {
 146       const char *local_dir = nis_local_directory ();
 147       size_t local_dir_len = strlen (local_dir);
 148       static const char prefix[] = "networks.org_dir.";
 149
 150       char *p = malloc (sizeof (prefix) + local_dir_len);
 151       if (tablename_val == NULL)
 152         {
 153           *errnop = errno;
 154           return NSS_STATUS_TRYAGAIN;
 155         }
 156
 157       memcpy (__stpcpy (p, prefix), local_dir, local_dir_len + 1);
 158
 159       tablename_len = sizeof (prefix) - 1 + local_dir_len;
 160
 161       atomic_write_barrier ();
 162
 163       tablename_val = p;
 164     }
 165
 166   return NSS_STATUS_SUCCESS;
 167 }
 168
 169 enum nss_status
 170 _nss_nisplus_setnetent (int stayopen)
 171 {
 172   enum nss_status status = NSS_STATUS_SUCCESS;
 173
 174   __libc_lock_lock (lock);
 175
 176   if (result != NULL)
 177     {
 178       nis_freeresult (result);
 179       result = NULL;
 180     }
 181
 182   if (tablename_val == NULL)
 183     {
 184       int err;
 185       status = _nss_create_tablename (&err);
 186     }
 187
 188   __libc_lock_unlock (lock);
 189
 190   return status;
 191 }
 192
 193 enum nss_status
 194 _nss_nisplus_endnetent (void)
 195 {
 196   __libc_lock_lock (lock);
 197
 198   if (result != NULL)
 199     {
 200       nis_freeresult (result);
 201       result = NULL;
 202     }
 203
 204   __libc_lock_unlock (lock);
 205
 206   return NSS_STATUS_SUCCESS;
 207 }
 208
 209 static enum nss_status
 210 internal_nisplus_getnetent_r (struct netent *network, char *buffer,
 211                                size_t buflen, int *errnop, int *herrnop)
 212 {
 213   int parse_res;
 214
 215   /* Get the next entry until we found a correct one. */
 216   do
 217     {
 218       nis_result *saved_res;
 219
 220       if (result == NULL)
 221         {
 222           saved_res = NULL;
 223
 224           if (tablename_val == NULL)
 225             {
 226               enum nss_status status = _nss_create_tablename (errnop);
 227
 228               if (status != NSS_STATUS_SUCCESS)
 229                 return status;
 230             }
 231
 232           result = nis_first_entry (tablename_val);
 233           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 234             {
 235               int retval = niserr2nss (result->status);
 236               nis_freeresult (result);
 237               result = NULL;
 238               if (retval == NSS_STATUS_TRYAGAIN)
 239                 {
 240                   *herrnop = NETDB_INTERNAL;
 241                   *errnop = errno;
 242                   return retval;
 243                 }
 244               else
 245                 return retval;
 246             }
 247         }
 248       else
 249         {
 250           nis_result *res = nis_next_entry (tablename_val, &result->cookie);
 251           saved_res = result;
 252           result = res;
 253           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 254             {
 255               int retval = niserr2nss (result->status);
 256               nis_freeresult (result);
 257               result = saved_res;
 258               if (retval == NSS_STATUS_TRYAGAIN)
 259                 {
 260                   *herrnop = NETDB_INTERNAL;
 261                   *errnop = errno;
 262                 }
 263               return retval;
 264             }
 265         }
 266
 267       parse_res = _nss_nisplus_parse_netent (result, network, buffer,
 268                                              buflen, errnop);
 269       if (parse_res == -1)
 270         {
 271           *herrnop = NETDB_INTERNAL;
 272           return NSS_STATUS_TRYAGAIN;
 273         }
 274
 275     }
 276   while (!parse_res);
 277
 278   return NSS_STATUS_SUCCESS;
 279 }
 280
 281 enum nss_status
 282 _nss_nisplus_getnetent_r (struct netent *result, char *buffer,
 283                            size_t buflen, int *errnop, int *herrnop)
 284 {
 285   int status;
 286
 287   __libc_lock_lock (lock);
 288
 289   status = internal_nisplus_getnetent_r (result, buffer, buflen, errnop,
 290                                          herrnop);
 291
 292   __libc_lock_unlock (lock);
 293
 294   return status;
 295 }
 296
 297 enum nss_status
 298 _nss_nisplus_getnetbyname_r (const char *name, struct netent *network,
 299                               char *buffer, size_t buflen, int *errnop,
 300                              int *herrnop)
 301 {
 302   int parse_res, retval;
 303
 304   if (tablename_val == NULL)
 305     {
 306       __libc_lock_lock (lock);
 307
 308       enum nss_status status = _nss_create_tablename (errnop);
 309
 310       __libc_lock_unlock (lock);
 311
 312       if (status != NSS_STATUS_SUCCESS)
 313         return status;
 314     }
 315
 316   if (name == NULL)
 317     {
 318       *errnop = EINVAL;
 319       *herrnop = NETDB_INTERNAL;
 320       return NSS_STATUS_UNAVAIL;
 321     }
 322
 323   nis_result *result;
 324   char buf[strlen (name) + 10 + tablename_len];
 325   int olderr = errno;
 326
 327   /* Search at first in the alias list, and use the correct name
 328      for the next search */
 329   snprintf (buf, sizeof (buf), "[name=%s],%s", name, tablename_val);
 330   result = nis_list (buf, FOLLOW_LINKS | FOLLOW_PATH, NULL, NULL);
 331
 332   if (result != NULL)
 333     {
 334       char *bufptr = buf;
 335
 336       /* If we do not find it, try it as original name. But if the
 337          database is correct, we should find it in the first case, too */
 338       if ((result->status != NIS_SUCCESS
 339            && result->status != NIS_S_SUCCESS)
 340           || __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ
 341           || strcmp (result->objects.objects_val[0].EN_data.en_type,
 342                      "networks_tbl") != 0
 343           || (result->objects.objects_val[0].EN_data.en_cols.en_cols_len
 344               < 3))
 345         snprintf (buf, sizeof (buf), "[cname=%s],%s", name, tablename_val);
 346       else
 347         {
 348           /* We need to allocate a new buffer since there is no
 349              guarantee the returned name has a length limit.  */
 350           const char *entryval = NISENTRYVAL (0, 0, result);
 351           size_t buflen = strlen (entryval) + 10 + tablename_len;
 352           bufptr = alloca (buflen);
 353           snprintf (bufptr, buflen, "[cname=%s],%s",
 354                     entryval, tablename_val);
 355         }
 356
 357       nis_freeresult (result);
 358       result = nis_list (bufptr, FOLLOW_LINKS | FOLLOW_PATH, NULL, NULL);
 359     }
 360
 361   if (result == NULL)
 362     {
 363       __set_errno (ENOMEM);
 364       return NSS_STATUS_TRYAGAIN;
 365     }
 366
 367   retval = niserr2nss (result->status);
 368   if (__builtin_expect (retval != NSS_STATUS_SUCCESS, 0))
 369     {
 370       if (retval == NSS_STATUS_TRYAGAIN)
 371         {
 372           *errnop = errno;
 373           *herrnop = NETDB_INTERNAL;
 374         }
 375       else
 376         __set_errno (olderr);
 377       nis_freeresult (result);
 378       return retval;
 379     }
 380
 381   parse_res = _nss_nisplus_parse_netent (result, network, buffer, buflen,
 382                                          errnop);
 383
 384   nis_freeresult (result);
 385
 386   if (parse_res > 0)
 387     return NSS_STATUS_SUCCESS;
 388
 389   *herrnop = NETDB_INTERNAL;
 390   if (parse_res == -1)
 391     {
 392       *errnop = ERANGE;
 393       return NSS_STATUS_TRYAGAIN;
 394     }
 395
 396   __set_errno (olderr);
 397   return NSS_STATUS_NOTFOUND;
 398 }
 399
 400 /* XXX type is ignored, SUN's NIS+ table doesn't support it */
 401 enum nss_status
 402 _nss_nisplus_getnetbyaddr_r (uint32_t addr, const int type,
 403                              struct netent *network, char *buffer,
 404                              size_t buflen, int *errnop, int *herrnop)
 405 {
 406   if (tablename_val == NULL)
 407     {
 408       __libc_lock_lock (lock);
 409
 410       enum nss_status status = _nss_create_tablename (errnop);
 411
 412       __libc_lock_unlock (lock);
 413
 414       if (status != NSS_STATUS_SUCCESS)
 415         return status;
 416     }
 417
 418   {
 419     int parse_res, retval;
 420     nis_result *result;
 421     char buf[1024 + tablename_len];
 422     struct in_addr in;
 423     char buf2[256];
 424     int b2len;
 425     int olderr = errno;
 426
 427     in = inet_makeaddr (addr, 0);
 428     strcpy (buf2, inet_ntoa (in));
 429     b2len = strlen (buf2);
 430
 431     while (1)
 432       {
 433         sprintf (buf, "[addr=%s],%s", buf2, tablename_val);
 434         result = nis_list (buf, EXPAND_NAME, NULL, NULL);
 435
 436         if (result == NULL)
 437           {
 438             __set_errno (ENOMEM);
 439             return NSS_STATUS_TRYAGAIN;
 440           }
 441         retval = niserr2nss (result->status);
 442         if (retval != NSS_STATUS_SUCCESS)
 443           {
 444             if (buf2[b2len -2] == '.' && buf2[b2len -1] == '0')
 445               {
 446                 /* Try again, but with trailing dot(s)
 447                    removed (one by one) */
 448                 buf2[b2len - 2] = '\0';
 449                 b2len -= 2;
 450                 continue;
 451               }
 452             else
 453               return NSS_STATUS_NOTFOUND;
 454
 455             if (retval == NSS_STATUS_TRYAGAIN)
 456               {
 457                 *errnop = errno;
 458                 *herrnop = NETDB_INTERNAL;
 459               }
 460             else
 461               __set_errno (olderr);
 462             nis_freeresult (result);
 463             return retval;
 464           }
 465
 466         parse_res = _nss_nisplus_parse_netent (result, network, buffer,
 467                                                buflen, errnop);
 468
 469         nis_freeresult (result);
 470
 471         if (parse_res > 0)
 472           return NSS_STATUS_SUCCESS;
 473
 474         *herrnop = NETDB_INTERNAL;
 475         if (parse_res == -1)
 476           {
 477             *errnop = ERANGE;
 478             return NSS_STATUS_TRYAGAIN;
 479           }
 480         else
 481           {
 482             __set_errno (olderr);
 483             return NSS_STATUS_NOTFOUND;
 484           }
 485       }
 486   }
 487 }