nis/nss_nisplus/nisplus-network.c

   1 /* Copyright (C) 1997,1998,2000-2003,2005,2006 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         (NIS_RES_OBJECT (res)[idx].EN_data.en_cols.en_cols_val[col].ec_value.ec_value_val)
  41
  42 #define NISENTRYLEN(idx, col, res) \
  43         (NIS_RES_OBJECT (res)[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 (NIS_RES_OBJECT (result)) != NIS_ENTRY_OBJ
  58       || strcmp (NIS_RES_OBJECT (result)[0].EN_data.en_type,
  59                  "networks_tbl") != 0
  60       || NIS_RES_OBJECT (result)[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   size_t len = strlen (first_unused) + 1;
  76   room_left -= len;
  77   first_unused += len;
  78
  79   network->n_addrtype = 0;
  80   network->n_net = inet_network (NISENTRYVAL (0, 2, result));
  81
  82   /* XXX Rewrite at some point to allocate the array first and then
  83      copy the strings.  It wasteful to first concatenate the strings
  84      to just split them again later.  */
  85   char *line = first_unused;
  86   for (unsigned int i = 0; i < NIS_RES_NUMOBJ (result); ++i)
  87     {
  88       if (strcmp (NISENTRYVAL (i, 1, result), network->n_name) != 0)
  89         {
  90           if (NISENTRYLEN (i, 1, result) + 2 > room_left)
  91             goto no_more_room;
  92
  93           *first_unused++ = ' ';
  94           first_unused = __stpncpy (first_unused, NISENTRYVAL (i, 1, result),
  95                                     NISENTRYLEN (i, 1, result));
  96           room_left -= (NISENTRYLEN (i, 1, result) + 1);
  97         }
  98     }
  99   *first_unused++ = '\0';
 100
 101   /* Adjust the pointer so it is aligned for
 102      storing pointers.  */
 103   size_t adjust = ((__alignof__ (char *)
 104                     - (first_unused - (char *) 0) % __alignof__ (char *))
 105                    % __alignof__ (char *));
 106   if (room_left < adjust + sizeof (char *))
 107     goto no_more_room;
 108   first_unused += adjust;
 109   room_left -= adjust;
 110   network->n_aliases = (char **) first_unused;
 111
 112   /* For the terminating NULL pointer.  */
 113   room_left -= sizeof (char *);
 114
 115   unsigned int i = 0;
 116   while (*line != '\0')
 117     {
 118       /* Skip leading blanks.  */
 119       while (isspace (*line))
 120         ++line;
 121
 122       if (*line == '\0')
 123         break;
 124
 125       if (room_left < sizeof (char *))
 126         goto no_more_room;
 127
 128       room_left -= sizeof (char *);
 129       network->n_aliases[i++] = line;
 130
 131       while (*line != '\0' && *line != ' ')
 132         ++line;
 133
 134       if (*line == ' ')
 135         *line++ = '\0';
 136     }
 137   network->n_aliases[i] = NULL;
 138
 139   return 1;
 140 }
 141
 142
 143 static enum nss_status
 144 _nss_create_tablename (int *errnop)
 145 {
 146   if (tablename_val == NULL)
 147     {
 148       const char *local_dir = nis_local_directory ();
 149       size_t local_dir_len = strlen (local_dir);
 150       static const char prefix[] = "networks.org_dir.";
 151
 152       char *p = malloc (sizeof (prefix) + local_dir_len);
 153       if (p == NULL)
 154         {
 155           *errnop = errno;
 156           return NSS_STATUS_TRYAGAIN;
 157         }
 158
 159       memcpy (__stpcpy (p, prefix), local_dir, local_dir_len + 1);
 160
 161       tablename_len = sizeof (prefix) - 1 + local_dir_len;
 162
 163       atomic_write_barrier ();
 164
 165       tablename_val = p;
 166     }
 167
 168   return NSS_STATUS_SUCCESS;
 169 }
 170
 171 enum nss_status
 172 _nss_nisplus_setnetent (int stayopen)
 173 {
 174   enum nss_status status = NSS_STATUS_SUCCESS;
 175
 176   __libc_lock_lock (lock);
 177
 178   if (result != NULL)
 179     {
 180       nis_freeresult (result);
 181       result = NULL;
 182     }
 183
 184   if (tablename_val == NULL)
 185     {
 186       int err;
 187       status = _nss_create_tablename (&err);
 188     }
 189
 190   __libc_lock_unlock (lock);
 191
 192   return status;
 193 }
 194
 195 enum nss_status
 196 _nss_nisplus_endnetent (void)
 197 {
 198   __libc_lock_lock (lock);
 199
 200   if (result != NULL)
 201     {
 202       nis_freeresult (result);
 203       result = NULL;
 204     }
 205
 206   __libc_lock_unlock (lock);
 207
 208   return NSS_STATUS_SUCCESS;
 209 }
 210
 211 static enum nss_status
 212 internal_nisplus_getnetent_r (struct netent *network, char *buffer,
 213                                size_t buflen, int *errnop, int *herrnop)
 214 {
 215   int parse_res;
 216
 217   /* Get the next entry until we found a correct one. */
 218   do
 219     {
 220       nis_result *saved_res;
 221
 222       if (result == NULL)
 223         {
 224           saved_res = NULL;
 225
 226           if (tablename_val == NULL)
 227             {
 228               enum nss_status status = _nss_create_tablename (errnop);
 229
 230               if (status != NSS_STATUS_SUCCESS)
 231                 return status;
 232             }
 233
 234           result = nis_first_entry (tablename_val);
 235           if (result == NULL)
 236             {
 237               *errnop = errno;
 238               return NSS_STATUS_TRYAGAIN;
 239             }
 240           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 241             {
 242               int retval = niserr2nss (result->status);
 243               nis_freeresult (result);
 244               result = NULL;
 245               if (retval == NSS_STATUS_TRYAGAIN)
 246                 {
 247                   *herrnop = NETDB_INTERNAL;
 248                   *errnop = errno;
 249                   return retval;
 250                 }
 251               else
 252                 return retval;
 253             }
 254         }
 255       else
 256         {
 257           saved_res = result;
 258           result = nis_next_entry (tablename_val, &result->cookie);
 259           if (result == NULL)
 260             {
 261               *errnop = errno;
 262               return NSS_STATUS_TRYAGAIN;
 263             }
 264           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 265             {
 266               int retval = niserr2nss (result->status);
 267               nis_freeresult (result);
 268               result = saved_res;
 269               if (retval == NSS_STATUS_TRYAGAIN)
 270                 {
 271                   *herrnop = NETDB_INTERNAL;
 272                   *errnop = errno;
 273                 }
 274               return retval;
 275             }
 276         }
 277
 278       parse_res = _nss_nisplus_parse_netent (result, network, buffer,
 279                                              buflen, errnop);
 280       if (parse_res == -1)
 281         {
 282           *herrnop = NETDB_INTERNAL;
 283           return NSS_STATUS_TRYAGAIN;
 284         }
 285
 286     }
 287   while (!parse_res);
 288
 289   return NSS_STATUS_SUCCESS;
 290 }
 291
 292 enum nss_status
 293 _nss_nisplus_getnetent_r (struct netent *result, char *buffer,
 294                            size_t buflen, int *errnop, int *herrnop)
 295 {
 296   int status;
 297
 298   __libc_lock_lock (lock);
 299
 300   status = internal_nisplus_getnetent_r (result, buffer, buflen, errnop,
 301                                          herrnop);
 302
 303   __libc_lock_unlock (lock);
 304
 305   return status;
 306 }
 307
 308 enum nss_status
 309 _nss_nisplus_getnetbyname_r (const char *name, struct netent *network,
 310                               char *buffer, size_t buflen, int *errnop,
 311                              int *herrnop)
 312 {
 313   int parse_res, retval;
 314
 315   if (tablename_val == NULL)
 316     {
 317       __libc_lock_lock (lock);
 318
 319       enum nss_status status = _nss_create_tablename (errnop);
 320
 321       __libc_lock_unlock (lock);
 322
 323       if (status != NSS_STATUS_SUCCESS)
 324         return status;
 325     }
 326
 327   if (name == NULL)
 328     {
 329       *errnop = EINVAL;
 330       *herrnop = NETDB_INTERNAL;
 331       return NSS_STATUS_UNAVAIL;
 332     }
 333
 334   nis_result *result;
 335   char buf[strlen (name) + 10 + tablename_len];
 336   int olderr = errno;
 337
 338   /* Search at first in the alias list, and use the correct name
 339      for the next search */
 340   snprintf (buf, sizeof (buf), "[name=%s],%s", name, tablename_val);
 341   result = nis_list (buf, FOLLOW_LINKS | FOLLOW_PATH, NULL, NULL);
 342
 343   if (result != NULL)
 344     {
 345       char *bufptr = buf;
 346
 347       /* If we do not find it, try it as original name. But if the
 348          database is correct, we should find it in the first case, too */
 349       if ((result->status != NIS_SUCCESS
 350            && result->status != NIS_S_SUCCESS)
 351           || __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ
 352           || strcmp (result->objects.objects_val[0].EN_data.en_type,
 353                      "networks_tbl") != 0
 354           || (result->objects.objects_val[0].EN_data.en_cols.en_cols_len
 355               < 3))
 356         snprintf (buf, sizeof (buf), "[cname=%s],%s", name, tablename_val);
 357       else
 358         {
 359           /* We need to allocate a new buffer since there is no
 360              guarantee the returned name has a length limit.  */
 361           const char *entryval = NISENTRYVAL (0, 0, result);
 362           size_t buflen = strlen (entryval) + 10 + tablename_len;
 363           bufptr = alloca (buflen);
 364           snprintf (bufptr, buflen, "[cname=%s],%s",
 365                     entryval, tablename_val);
 366         }
 367
 368       nis_freeresult (result);
 369       result = nis_list (bufptr, FOLLOW_LINKS | FOLLOW_PATH, NULL, NULL);
 370     }
 371
 372   if (result == NULL)
 373     {
 374       __set_errno (ENOMEM);
 375       return NSS_STATUS_TRYAGAIN;
 376     }
 377
 378   retval = niserr2nss (result->status);
 379   if (__builtin_expect (retval != NSS_STATUS_SUCCESS, 0))
 380     {
 381       if (retval == NSS_STATUS_TRYAGAIN)
 382         {
 383           *errnop = errno;
 384           *herrnop = NETDB_INTERNAL;
 385         }
 386       else
 387         __set_errno (olderr);
 388       nis_freeresult (result);
 389       return retval;
 390     }
 391
 392   parse_res = _nss_nisplus_parse_netent (result, network, buffer, buflen,
 393                                          errnop);
 394
 395   nis_freeresult (result);
 396
 397   if (parse_res > 0)
 398     return NSS_STATUS_SUCCESS;
 399
 400   *herrnop = NETDB_INTERNAL;
 401   if (parse_res == -1)
 402     {
 403       *errnop = ERANGE;
 404       return NSS_STATUS_TRYAGAIN;
 405     }
 406
 407   __set_errno (olderr);
 408   return NSS_STATUS_NOTFOUND;
 409 }
 410
 411 /* XXX type is ignored, SUN's NIS+ table doesn't support it */
 412 enum nss_status
 413 _nss_nisplus_getnetbyaddr_r (uint32_t addr, const int type,
 414                              struct netent *network, char *buffer,
 415                              size_t buflen, int *errnop, int *herrnop)
 416 {
 417   if (tablename_val == NULL)
 418     {
 419       __libc_lock_lock (lock);
 420
 421       enum nss_status status = _nss_create_tablename (errnop);
 422
 423       __libc_lock_unlock (lock);
 424
 425       if (status != NSS_STATUS_SUCCESS)
 426         return status;
 427     }
 428
 429   {
 430     char buf[27 + tablename_len];
 431     char buf2[18];
 432     int olderr = errno;
 433
 434     struct in_addr in = inet_makeaddr (addr, 0);
 435     strcpy (buf2, inet_ntoa (in));
 436     size_t b2len = strlen (buf2);
 437
 438     while (1)
 439       {
 440         snprintf (buf, sizeof (buf), "[addr=%s],%s", buf2, tablename_val);
 441         nis_result *result = nis_list (buf, EXPAND_NAME, NULL, NULL);
 442
 443         if (result == NULL)
 444           {
 445             __set_errno (ENOMEM);
 446             return NSS_STATUS_TRYAGAIN;
 447           }
 448         enum nss_status retval = niserr2nss (result->status);
 449         if (__builtin_expect (retval != NSS_STATUS_SUCCESS, 0))
 450           {
 451             if (b2len > 2 && buf2[b2len - 2] == '.' && buf2[b2len - 1] == '0')
 452               {
 453                 /* Try again, but with trailing dot(s)
 454                    removed (one by one) */
 455                 buf2[b2len - 2] = '\0';
 456                 b2len -= 2;
 457                 nis_freeresult (result);
 458                 continue;
 459               }
 460
 461             if (retval == NSS_STATUS_TRYAGAIN)
 462               {
 463                 *errnop = errno;
 464                 *herrnop = NETDB_INTERNAL;
 465               }
 466             else
 467               __set_errno (olderr);
 468             nis_freeresult (result);
 469             return retval;
 470           }
 471
 472         int parse_res = _nss_nisplus_parse_netent (result, network, buffer,
 473                                                    buflen, errnop);
 474
 475         nis_freeresult (result);
 476
 477         if (parse_res > 0)
 478           return NSS_STATUS_SUCCESS;
 479
 480         *herrnop = NETDB_INTERNAL;
 481         if (parse_res == -1)
 482           {
 483             *errnop = ERANGE;
 484             return NSS_STATUS_TRYAGAIN;
 485           }
 486         else
 487           {
 488             __set_errno (olderr);
 489             return NSS_STATUS_NOTFOUND;
 490           }
 491       }
 492   }
 493 }