nis/nss_nisplus/nisplus-service.c

   1 /* Copyright (C) 1997, 1998, 1999, 2001, 2002, 2003, 2005, 2006, 2007
   2    Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Thorsten Kukuk <kukuk@suse.de>, 1997.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 #include <atomic.h>
  22 #include <ctype.h>
  23 #include <errno.h>
  24 #include <netdb.h>
  25 #include <nss.h>
  26 #include <string.h>
  27 #include <rpcsvc/nis.h>
  28 #include <bits/libc-lock.h>
  29
  30 #include "nss-nisplus.h"
  31
  32 __libc_lock_define_initialized (static, lock);
  33
  34 static nis_result *result;
  35 static nis_name tablename_val;
  36 static u_long tablename_len;
  37
  38 #define NISENTRYVAL(idx, col, res) \
  39   (NIS_RES_OBJECT (res)[idx].EN_data.en_cols.en_cols_val[col].ec_value.ec_value_val)
  40
  41 #define NISENTRYLEN(idx, col, res) \
  42     (NIS_RES_OBJECT (res)[idx].EN_data.en_cols.en_cols_val[col].ec_value.ec_value_len)
  43
  44
  45 static int
  46 _nss_nisplus_parse_servent (nis_result *result, struct servent *serv,
  47                             char *buffer, size_t buflen, int *errnop)
  48 {
  49   char *first_unused = buffer;
  50   size_t room_left = buflen;
  51
  52   if (result == NULL)
  53     return 0;
  54
  55   if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS)
  56       || __type_of (NIS_RES_OBJECT (result)) != NIS_ENTRY_OBJ
  57       || strcmp (NIS_RES_OBJECT (result)->EN_data.en_type, "services_tbl") != 0
  58       || NIS_RES_OBJECT (result)->EN_data.en_cols.en_cols_len < 4)
  59     return 0;
  60
  61   if (NISENTRYLEN (0, 0, result) >= room_left)
  62     {
  63     no_more_room:
  64       *errnop = ERANGE;
  65       return -1;
  66     }
  67   strncpy (first_unused, NISENTRYVAL (0, 0, result),
  68            NISENTRYLEN (0, 0, result));
  69   first_unused[NISENTRYLEN (0, 0, result)] = '\0';
  70   serv->s_name = first_unused;
  71   size_t len = strlen (first_unused) + 1;
  72   room_left -= len;
  73   first_unused += len;
  74
  75   if (NISENTRYLEN (0, 2, result) >= room_left)
  76     goto no_more_room;
  77   strncpy (first_unused, NISENTRYVAL (0, 2, result),
  78            NISENTRYLEN (0, 2, result));
  79   first_unused[NISENTRYLEN (0, 2, result)] = '\0';
  80   serv->s_proto = first_unused;
  81   len = strlen (first_unused) + 1;
  82   room_left -= len;
  83   first_unused += len;
  84
  85   serv->s_port = htons (atoi (NISENTRYVAL (0, 3, result)));
  86
  87   /* XXX Rewrite at some point to allocate the array first and then
  88      copy the strings.  It wasteful to first concatenate the strings
  89      to just split them again later.  */
  90   char *line = first_unused;
  91   for (unsigned int i = 0; i < NIS_RES_NUMOBJ (result); ++i)
  92     {
  93       if (strcmp (NISENTRYVAL (i, 1, result), serv->s_name) != 0)
  94         {
  95           if (NISENTRYLEN (i, 1, result) + 2 > room_left)
  96             goto no_more_room;
  97           *first_unused++ = ' ';
  98           first_unused = __stpncpy (first_unused, NISENTRYVAL (i, 1, result),
  99                                     NISENTRYLEN (i, 1, result));
 100           room_left -= NISENTRYLEN (i, 1, result) + 1;
 101         }
 102     }
 103   *first_unused++ = '\0';
 104
 105   /* Adjust the pointer so it is aligned for
 106      storing pointers.  */
 107   size_t adjust = ((__alignof__ (char *)
 108                     - (first_unused - (char *) 0) % __alignof__ (char *))
 109                    % __alignof__ (char *));
 110   if (room_left < adjust + sizeof (char *))
 111     goto no_more_room;
 112   first_unused += adjust;
 113   room_left -= adjust;
 114   serv->s_aliases = (char **) first_unused;
 115
 116   /* For the terminating NULL pointer.  */
 117   room_left -= (sizeof (char *));
 118
 119   unsigned int i = 0;
 120   while (*line != '\0')
 121     {
 122       /* Skip leading blanks.  */
 123       while (isspace (*line))
 124         ++line;
 125
 126       if (*line == '\0')
 127         break;
 128
 129       if (room_left < sizeof (char *))
 130         goto no_more_room;
 131
 132       room_left -= sizeof (char *);
 133       serv->s_aliases[i++] = line;
 134
 135       while (*line != '\0' && *line != ' ')
 136         ++line;
 137
 138       if (*line == ' ')
 139         *line++ = '\0';
 140     }
 141   serv->s_aliases[i] = NULL;
 142
 143   return 1;
 144 }
 145
 146
 147 static enum nss_status
 148 _nss_create_tablename (int *errnop)
 149 {
 150   if (tablename_val == NULL)
 151     {
 152       const char *local_dir = nis_local_directory ();
 153       size_t local_dir_len = strlen (local_dir);
 154       static const char prefix[] = "services.org_dir.";
 155
 156       char *p = malloc (sizeof (prefix) + local_dir_len);
 157       if (p == NULL)
 158         {
 159           *errnop = errno;
 160           return NSS_STATUS_TRYAGAIN;
 161         }
 162
 163       memcpy (__stpcpy (p, prefix), local_dir, local_dir_len + 1);
 164
 165       tablename_len = sizeof (prefix) - 1 + local_dir_len;
 166
 167       atomic_write_barrier ();
 168
 169       tablename_val = p;
 170     }
 171
 172   return NSS_STATUS_SUCCESS;
 173 }
 174
 175
 176 enum nss_status
 177 _nss_nisplus_setservent (int stayopen)
 178 {
 179   enum nss_status status = NSS_STATUS_SUCCESS;
 180   int err;
 181
 182   __libc_lock_lock (lock);
 183
 184   if (result != NULL)
 185     {
 186       nis_freeresult (result);
 187       result = NULL;
 188     }
 189
 190   if (tablename_val == NULL)
 191     status = _nss_create_tablename (&err);
 192
 193   __libc_lock_unlock (lock);
 194
 195   return status;
 196 }
 197
 198 enum nss_status
 199 _nss_nisplus_endservent (void)
 200 {
 201   __libc_lock_lock (lock);
 202
 203   if (result != NULL)
 204     {
 205       nis_freeresult (result);
 206       result = NULL;
 207     }
 208
 209   __libc_lock_unlock (lock);
 210
 211   return NSS_STATUS_SUCCESS;
 212 }
 213
 214 static enum nss_status
 215 internal_nisplus_getservent_r (struct servent *serv, char *buffer,
 216                                size_t buflen, int *errnop)
 217 {
 218   int parse_res;
 219
 220   /* Get the next entry until we found a correct one. */
 221   do
 222     {
 223       nis_result *saved_res;
 224
 225       if (result == NULL)
 226         {
 227           saved_res = NULL;
 228           if (tablename_val == NULL)
 229             {
 230               enum nss_status status = _nss_create_tablename (errnop);
 231
 232               if (status != NSS_STATUS_SUCCESS)
 233                 return status;
 234             }
 235
 236           result = nis_first_entry (tablename_val);
 237           if (result == NULL)
 238             {
 239               *errnop = errno;
 240               return NSS_STATUS_TRYAGAIN;
 241             }
 242           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 243             return niserr2nss (result->status);
 244         }
 245       else
 246         {
 247           saved_res = result;
 248           result = nis_next_entry (tablename_val, &result->cookie);
 249           if (result == NULL)
 250             {
 251               *errnop = errno;
 252               return NSS_STATUS_TRYAGAIN;
 253             }
 254           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 255             {
 256               nis_freeresult (saved_res);
 257               return niserr2nss (result->status);
 258             }
 259         }
 260
 261       parse_res = _nss_nisplus_parse_servent (result, serv, buffer,
 262                                               buflen, errnop);
 263       if (__builtin_expect (parse_res == -1, 0))
 264         {
 265           nis_freeresult (result);
 266           result = saved_res;
 267           *errnop = ERANGE;
 268           return NSS_STATUS_TRYAGAIN;
 269         }
 270       else
 271         {
 272           if (saved_res)
 273             nis_freeresult (saved_res);
 274         }
 275     }
 276   while (!parse_res);
 277
 278   return NSS_STATUS_SUCCESS;
 279 }
 280
 281 enum nss_status
 282 _nss_nisplus_getservent_r (struct servent *result, char *buffer,
 283                            size_t buflen, int *errnop)
 284 {
 285   __libc_lock_lock (lock);
 286
 287   int status = internal_nisplus_getservent_r (result, buffer, buflen, errnop);
 288
 289   __libc_lock_unlock (lock);
 290
 291   return status;
 292 }
 293
 294 enum nss_status
 295 _nss_nisplus_getservbyname_r (const char *name, const char *protocol,
 296                               struct servent *serv,
 297                               char *buffer, size_t buflen, int *errnop)
 298 {
 299   if (tablename_val == NULL)
 300     {
 301       __libc_lock_lock (lock);
 302
 303       enum nss_status status = _nss_create_tablename (errnop);
 304
 305       __libc_lock_unlock (lock);
 306
 307       if (status != NSS_STATUS_SUCCESS)
 308         return status;
 309     }
 310
 311   if (name == NULL || protocol == NULL)
 312     {
 313       *errnop = EINVAL;
 314       return NSS_STATUS_NOTFOUND;
 315     }
 316
 317   size_t protocol_len = strlen (protocol);
 318   char buf[strlen (name) + protocol_len + 17 + tablename_len];
 319   int olderr = errno;
 320
 321   /* Search at first in the alias list, and use the correct name
 322      for the next search */
 323   snprintf (buf, sizeof (buf), "[name=%s,proto=%s],%s", name, protocol,
 324             tablename_val);
 325   nis_result *result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS | USE_DGRAM,
 326                                  NULL, NULL);
 327
 328   if (result != NULL)
 329     {
 330       char *bufptr = buf;
 331
 332       /* If we did not find it, try it as original name. But if the
 333          database is correct, we should find it in the first case, too */
 334       if ((result->status != NIS_SUCCESS
 335            && result->status != NIS_S_SUCCESS)
 336           || __type_of (NIS_RES_OBJECT (result)) != NIS_ENTRY_OBJ
 337           || strcmp (NIS_RES_OBJECT (result)->EN_data.en_type,
 338                      "services_tbl") != 0
 339           || NIS_RES_OBJECT (result)->EN_data.en_cols.en_cols_len < 4)
 340         snprintf (buf, sizeof (buf), "[cname=%s,proto=%s],%s", name, protocol,
 341                   tablename_val);
 342       else
 343         {
 344           /* We need to allocate a new buffer since there is no
 345              guarantee the returned name has a length limit.  */
 346           const char *entryval = NISENTRYVAL(0, 0, result);
 347           size_t buflen = (strlen (entryval) + protocol_len + 17
 348                            + tablename_len);
 349           bufptr = alloca (buflen);
 350           snprintf (bufptr, buflen, "[cname=%s,proto=%s],%s",
 351                     entryval, protocol, tablename_val);
 352         }
 353
 354       nis_freeresult (result);
 355       result = nis_list (bufptr, FOLLOW_PATH | FOLLOW_LINKS | USE_DGRAM,
 356                          NULL, NULL);
 357     }
 358
 359   if (result == NULL)
 360     {
 361       *errnop = ENOMEM;
 362       return NSS_STATUS_TRYAGAIN;
 363     }
 364
 365   if (__builtin_expect (niserr2nss (result->status) != NSS_STATUS_SUCCESS, 0))
 366     {
 367       enum nss_status status = niserr2nss (result->status);
 368
 369       __set_errno (olderr);
 370
 371       nis_freeresult (result);
 372       return status;
 373     }
 374
 375   int parse_res = _nss_nisplus_parse_servent (result, serv, buffer, buflen,
 376                                               errnop);
 377   nis_freeresult (result);
 378
 379   if (__builtin_expect (parse_res < 1, 0))
 380     {
 381       if (parse_res == -1)
 382         {
 383           *errnop = ERANGE;
 384           return NSS_STATUS_TRYAGAIN;
 385         }
 386       else
 387         {
 388           __set_errno (olderr);
 389           return NSS_STATUS_NOTFOUND;
 390         }
 391     }
 392
 393   return NSS_STATUS_SUCCESS;
 394 }
 395
 396 enum nss_status
 397 _nss_nisplus_getservbyport_r (const int number, const char *protocol,
 398                               struct servent *serv,
 399                               char *buffer, size_t buflen, int *errnop)
 400 {
 401   if (tablename_val == NULL)
 402     {
 403       __libc_lock_lock (lock);
 404
 405       enum nss_status status = _nss_create_tablename (errnop);
 406
 407       __libc_lock_unlock (lock);
 408
 409       if (status != NSS_STATUS_SUCCESS)
 410         return status;
 411     }
 412
 413   if (protocol == NULL)
 414     {
 415       *errnop = EINVAL;
 416       return NSS_STATUS_NOTFOUND;
 417     }
 418
 419   char buf[17 + 3 * sizeof (int) + strlen (protocol) + tablename_len];
 420   int olderr = errno;
 421
 422   snprintf (buf, sizeof (buf), "[port=%d,proto=%s],%s",
 423             number, protocol, tablename_val);
 424
 425   nis_result *result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS | USE_DGRAM,
 426                                  NULL, NULL);
 427
 428   if (result == NULL)
 429     {
 430       *errnop = ENOMEM;
 431       return NSS_STATUS_TRYAGAIN;
 432     }
 433
 434   if (__builtin_expect (niserr2nss (result->status) != NSS_STATUS_SUCCESS, 0))
 435     {
 436       enum nss_status status = niserr2nss (result->status);
 437
 438       __set_errno (olderr);
 439
 440       nis_freeresult (result);
 441       return status;
 442     }
 443
 444   int parse_res = _nss_nisplus_parse_servent (result, serv, buffer, buflen,
 445                                               errnop);
 446   nis_freeresult (result);
 447
 448   if (__builtin_expect (parse_res < 1, 0))
 449     {
 450       if (parse_res == -1)
 451         {
 452           *errnop = ERANGE;
 453           return NSS_STATUS_TRYAGAIN;
 454         }
 455       else
 456         {
 457           __set_errno (olderr);
 458           return NSS_STATUS_NOTFOUND;
 459         }
 460     }
 461
 462   return NSS_STATUS_SUCCESS;
 463 }