nis/nss_nisplus/nisplus-rpc.c

   1 /* Copyright (C) 1997, 1998, 2001, 2002, 2003, 2005, 2006
   2    Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.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 <nss.h>
  25 #include <string.h>
  26 #include <rpc/netdb.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_rpcent (nis_result *result, struct rpcent *rpc,
  47                            char *buffer, size_t buflen, int *errnop)
  48 {
  49   char *first_unused = buffer;
  50   size_t room_left = buflen;
  51   unsigned int i;
  52   char *line;
  53
  54
  55   if (result == NULL)
  56     return 0;
  57
  58   if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS)
  59       || __type_of (NIS_RES_OBJECT (result)) != NIS_ENTRY_OBJ
  60       || strcmp (NIS_RES_OBJECT (result)[0].EN_data.en_type, "rpc_tbl") != 0
  61       || NIS_RES_OBJECT (result)[0].EN_data.en_cols.en_cols_len < 3)
  62     return 0;
  63
  64   if (NISENTRYLEN (0, 0, result) >= room_left)
  65     {
  66     no_more_room:
  67       *errnop = ERANGE;
  68       return -1;
  69     }
  70   strncpy (first_unused, NISENTRYVAL (0, 0, result),
  71            NISENTRYLEN (0, 0, result));
  72   first_unused[NISENTRYLEN (0, 0, result)] = '\0';
  73   rpc->r_name = first_unused;
  74   size_t len = strlen (first_unused) + 1;
  75   room_left -= len;
  76   first_unused += len;
  77
  78   rpc->r_number = atoi (NISENTRYVAL (0, 2, result));
  79
  80   /* XXX Rewrite at some point to allocate the array first and then
  81      copy the strings.  It wasteful to first concatenate the strings
  82      to just split them again later.  */
  83   line = first_unused;
  84   for (i = 0; i < NIS_RES_NUMOBJ (result); ++i)
  85     {
  86       if (strcmp (NISENTRYVAL (i, 1, result), rpc->r_name) != 0)
  87         {
  88           if (NISENTRYLEN (i, 1, result) + 2 > room_left)
  89             goto no_more_room;
  90           *first_unused++ = ' ';
  91           first_unused = __stpncpy (first_unused, NISENTRYVAL (i, 1, result),
  92                                     NISENTRYLEN (i, 1, result));
  93           room_left -= NISENTRYLEN (i, 1, result) + 1;
  94         }
  95     }
  96   *first_unused++ = '\0';
  97
  98   /* Adjust the pointer so it is aligned for
  99      storing pointers.  */
 100   size_t adjust = ((__alignof__ (char *)
 101                     - (first_unused - (char *) 0) % __alignof__ (char *))
 102                    % __alignof__ (char *));
 103   if (room_left < adjust + sizeof (char *))
 104     goto no_more_room;
 105   first_unused += adjust;
 106   room_left -= adjust;
 107   rpc->r_aliases = (char **) first_unused;
 108
 109   /* For the terminating NULL pointer.  */
 110   room_left -= sizeof (char *);
 111
 112   i = 0;
 113   while (*line != '\0')
 114     {
 115       /* Skip leading blanks.  */
 116       while (isspace (*line))
 117         ++line;
 118
 119       if (*line == '\0')
 120         break;
 121
 122       if (room_left < sizeof (char *))
 123         goto no_more_room;
 124
 125       room_left -= sizeof (char *);
 126       rpc->r_aliases[i++] = line;
 127
 128       while (*line != '\0' && *line != ' ')
 129         ++line;
 130
 131       if (*line == ' ')
 132         *line++ = '\0';
 133     }
 134   rpc->r_aliases[i] = NULL;
 135
 136   return 1;
 137 }
 138
 139
 140 static enum nss_status
 141 _nss_create_tablename (int *errnop)
 142 {
 143   if (tablename_val == NULL)
 144     {
 145       const char *local_dir = nis_local_directory ();
 146       size_t local_dir_len = strlen (local_dir);
 147       static const char prefix[] = "rpc.org_dir.";
 148
 149       char *p = malloc (sizeof (prefix) + local_dir_len);
 150       if (p == NULL)
 151         {
 152           *errnop = errno;
 153           return NSS_STATUS_TRYAGAIN;
 154         }
 155
 156       memcpy (__stpcpy (p, prefix), local_dir, local_dir_len + 1);
 157
 158       tablename_len = sizeof (prefix) - 1 + local_dir_len;
 159
 160       atomic_write_barrier ();
 161
 162       tablename_val = p;
 163     }
 164
 165   return NSS_STATUS_SUCCESS;
 166 }
 167
 168
 169 enum nss_status
 170 _nss_nisplus_setrpcent (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_endrpcent (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_getrpcent_r (struct rpcent *rpc, char *buffer,
 211                               size_t buflen, int *errnop)
 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           if (tablename_val == NULL)
 224             {
 225               enum nss_status status =  _nss_create_tablename (errnop);
 226
 227               if (status != NSS_STATUS_SUCCESS)
 228                 return status;
 229             }
 230
 231           result = nis_first_entry (tablename_val);
 232           if (result == NULL)
 233             {
 234               *errnop = errno;
 235               return NSS_STATUS_TRYAGAIN;
 236             }
 237           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 238             return niserr2nss (result->status);
 239         }
 240       else
 241         {
 242           saved_res = result;
 243           result = nis_next_entry (tablename_val, &result->cookie);
 244           if (result == NULL)
 245             {
 246               *errnop = errno;
 247               return NSS_STATUS_TRYAGAIN;
 248             }
 249           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 250             {
 251               nis_freeresult (saved_res);
 252               return niserr2nss (result->status);
 253             }
 254         }
 255
 256       parse_res = _nss_nisplus_parse_rpcent (result, rpc, buffer,
 257                                              buflen, errnop);
 258       if (parse_res == -1)
 259         {
 260           nis_freeresult (result);
 261           result = saved_res;
 262           *errnop = ERANGE;
 263           return NSS_STATUS_TRYAGAIN;
 264         }
 265       else
 266         {
 267           if (saved_res)
 268             nis_freeresult (saved_res);
 269         }
 270     }
 271   while (!parse_res);
 272
 273   return NSS_STATUS_SUCCESS;
 274 }
 275
 276 enum nss_status
 277 _nss_nisplus_getrpcent_r (struct rpcent *result, char *buffer,
 278                           size_t buflen, int *errnop)
 279 {
 280   int status;
 281
 282   __libc_lock_lock (lock);
 283
 284   status = internal_nisplus_getrpcent_r (result, buffer, buflen, errnop);
 285
 286   __libc_lock_unlock (lock);
 287
 288   return status;
 289 }
 290
 291 enum nss_status
 292 _nss_nisplus_getrpcbyname_r (const char *name, struct rpcent *rpc,
 293                              char *buffer, size_t buflen, int *errnop)
 294 {
 295   int parse_res;
 296
 297   if (tablename_val == NULL)
 298     {
 299       __libc_lock_lock (lock);
 300
 301       enum nss_status status = _nss_create_tablename (errnop);
 302
 303       __libc_lock_unlock (lock);
 304
 305       if (status != NSS_STATUS_SUCCESS)
 306         return status;
 307     }
 308
 309   if (name == NULL)
 310     return NSS_STATUS_NOTFOUND;
 311
 312   char buf[strlen (name) + 10 + tablename_len];
 313   int olderr = errno;
 314
 315   /* Search at first in the alias list, and use the correct name
 316      for the next search */
 317   snprintf (buf, sizeof (buf), "[name=%s],%s", name, tablename_val);
 318   nis_result *result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 319
 320   if (result != NULL)
 321     {
 322       char *bufptr = buf;
 323
 324       /* If we did not find it, try it as original name. But if the
 325          database is correct, we should find it in the first case, too */
 326       if ((result->status != NIS_SUCCESS
 327            && result->status != NIS_S_SUCCESS)
 328           || __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ
 329           || strcmp (result->objects.objects_val->EN_data.en_type,
 330                      "rpc_tbl") != 0
 331           || result->objects.objects_val->EN_data.en_cols.en_cols_len < 3)
 332         snprintf (buf, sizeof (buf), "[cname=%s],%s", name, tablename_val);
 333       else
 334         {
 335           /* We need to allocate a new buffer since there is no
 336              guarantee the returned name has a length limit.  */
 337           const char *entryval = NISENTRYVAL (0, 0, result);
 338           size_t buflen = strlen (entryval) + 10 + tablename_len;
 339           bufptr = alloca (buflen);
 340           snprintf (bufptr, buflen, "[cname=%s],%s",
 341                     entryval, tablename_val);
 342         }
 343
 344       nis_freeresult (result);
 345       result = nis_list (bufptr, FOLLOW_PATH | FOLLOW_LINKS , NULL, NULL);
 346     }
 347
 348   if (result == NULL)
 349     {
 350       *errnop = ENOMEM;
 351       return NSS_STATUS_TRYAGAIN;
 352     }
 353
 354   if (__builtin_expect (niserr2nss (result->status) != NSS_STATUS_SUCCESS, 0))
 355     {
 356       enum nss_status status = niserr2nss (result->status);
 357
 358       __set_errno (olderr);
 359
 360       nis_freeresult (result);
 361       return status;
 362     }
 363
 364   parse_res = _nss_nisplus_parse_rpcent (result, rpc, buffer, buflen,
 365                                              errnop);
 366
 367   nis_freeresult (result);
 368
 369   if (parse_res < 1)
 370     {
 371       if (parse_res == -1)
 372         {
 373           *errnop = ERANGE;
 374           return NSS_STATUS_TRYAGAIN;
 375         }
 376
 377       __set_errno (olderr);
 378       return NSS_STATUS_NOTFOUND;
 379     }
 380
 381   return NSS_STATUS_SUCCESS;
 382 }
 383
 384 enum nss_status
 385 _nss_nisplus_getrpcbynumber_r (const int number, struct rpcent *rpc,
 386                                char *buffer, size_t buflen, int *errnop)
 387 {
 388   if (tablename_val == NULL)
 389     {
 390       __libc_lock_lock (lock);
 391
 392       enum nss_status status = _nss_create_tablename (errnop);
 393
 394       __libc_lock_unlock (lock);
 395
 396       if (status != NSS_STATUS_SUCCESS)
 397         return status;
 398     }
 399
 400   char buf[12 + 3 * sizeof (number) + tablename_len];
 401   int olderr = errno;
 402
 403   snprintf (buf, sizeof (buf), "[number=%d],%s", number, tablename_val);
 404
 405   nis_result *result = nis_list (buf, FOLLOW_LINKS | FOLLOW_PATH, NULL, NULL);
 406
 407   if (result == NULL)
 408     {
 409       *errnop = ENOMEM;
 410       return NSS_STATUS_TRYAGAIN;
 411     }
 412
 413   if (__builtin_expect (niserr2nss (result->status) != NSS_STATUS_SUCCESS,  0))
 414     {
 415       enum nss_status status = niserr2nss (result->status);
 416
 417       __set_errno (olderr);
 418
 419       nis_freeresult (result);
 420       return status;
 421     }
 422
 423   int parse_res = _nss_nisplus_parse_rpcent (result, rpc, buffer, buflen,
 424                                              errnop);
 425
 426   nis_freeresult (result);
 427
 428   if (parse_res < 1)
 429     {
 430       if (parse_res == -1)
 431         {
 432           *errnop = ERANGE;
 433           return NSS_STATUS_TRYAGAIN;
 434         }
 435       else
 436         {
 437           __set_errno (olderr);
 438           return NSS_STATUS_NOTFOUND;
 439         }
 440     }
 441
 442   return NSS_STATUS_SUCCESS;
 443 }