nis/nss_nisplus/nisplus-rpc.c

   1 /* Copyright (C) 1997, 1998, 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@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, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #include <atomic.h>
  21 #include <ctype.h>
  22 #include <errno.h>
  23 #include <nss.h>
  24 #include <string.h>
  25 #include <rpc/netdb.h>
  26 #include <rpcsvc/nis.h>
  27 #include <bits/libc-lock.h>
  28
  29 #include "nss-nisplus.h"
  30
  31 __libc_lock_define_initialized (static, lock)
  32
  33 static nis_result *result;
  34 static nis_name tablename_val;
  35 static u_long tablename_len;
  36
  37 #define NISENTRYVAL(idx, col, res) \
  38         (NIS_RES_OBJECT (res)[idx].EN_data.en_cols.en_cols_val[col].ec_value.ec_value_val)
  39
  40 #define NISENTRYLEN(idx, col, res) \
  41         (NIS_RES_OBJECT (res)[idx].EN_data.en_cols.en_cols_val[col].ec_value.ec_value_len)
  42
  43
  44 static int
  45 _nss_nisplus_parse_rpcent (nis_result *result, struct rpcent *rpc,
  46                            char *buffer, size_t buflen, int *errnop)
  47 {
  48   char *first_unused = buffer;
  49   size_t room_left = buflen;
  50   unsigned int i;
  51   char *line;
  52
  53
  54   if (result == NULL)
  55     return 0;
  56
  57   if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS)
  58       || __type_of (NIS_RES_OBJECT (result)) != NIS_ENTRY_OBJ
  59       || strcmp (NIS_RES_OBJECT (result)[0].EN_data.en_type, "rpc_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     no_more_room:
  66       *errnop = ERANGE;
  67       return -1;
  68     }
  69   strncpy (first_unused, NISENTRYVAL (0, 0, result),
  70            NISENTRYLEN (0, 0, result));
  71   first_unused[NISENTRYLEN (0, 0, result)] = '\0';
  72   rpc->r_name = first_unused;
  73   size_t len = strlen (first_unused) + 1;
  74   room_left -= len;
  75   first_unused += len;
  76
  77   rpc->r_number = atoi (NISENTRYVAL (0, 2, result));
  78
  79   /* XXX Rewrite at some point to allocate the array first and then
  80      copy the strings.  It wasteful to first concatenate the strings
  81      to just split them again later.  */
  82   line = first_unused;
  83   for (i = 0; i < NIS_RES_NUMOBJ (result); ++i)
  84     {
  85       if (strcmp (NISENTRYVAL (i, 1, result), rpc->r_name) != 0)
  86         {
  87           if (NISENTRYLEN (i, 1, result) + 2 > room_left)
  88             goto no_more_room;
  89           *first_unused++ = ' ';
  90           first_unused = __stpncpy (first_unused, NISENTRYVAL (i, 1, result),
  91                                     NISENTRYLEN (i, 1, result));
  92           room_left -= NISENTRYLEN (i, 1, result) + 1;
  93         }
  94     }
  95   *first_unused++ = '\0';
  96
  97   /* Adjust the pointer so it is aligned for
  98      storing pointers.  */
  99   size_t adjust = ((__alignof__ (char *)
 100                     - (first_unused - (char *) 0) % __alignof__ (char *))
 101                    % __alignof__ (char *));
 102   if (room_left < adjust + sizeof (char *))
 103     goto no_more_room;
 104   first_unused += adjust;
 105   room_left -= adjust;
 106   rpc->r_aliases = (char **) first_unused;
 107
 108   /* For the terminating NULL pointer.  */
 109   room_left -= sizeof (char *);
 110
 111   i = 0;
 112   while (*line != '\0')
 113     {
 114       /* Skip leading blanks.  */
 115       while (isspace (*line))
 116         ++line;
 117
 118       if (*line == '\0')
 119         break;
 120
 121       if (room_left < sizeof (char *))
 122         goto no_more_room;
 123
 124       room_left -= sizeof (char *);
 125       rpc->r_aliases[i++] = line;
 126
 127       while (*line != '\0' && *line != ' ')
 128         ++line;
 129
 130       if (*line == ' ')
 131         *line++ = '\0';
 132     }
 133   rpc->r_aliases[i] = NULL;
 134
 135   return 1;
 136 }
 137
 138
 139 static enum nss_status
 140 _nss_create_tablename (int *errnop)
 141 {
 142   if (tablename_val == NULL)
 143     {
 144       const char *local_dir = nis_local_directory ();
 145       size_t local_dir_len = strlen (local_dir);
 146       static const char prefix[] = "rpc.org_dir.";
 147
 148       char *p = malloc (sizeof (prefix) + local_dir_len);
 149       if (p == NULL)
 150         {
 151           *errnop = errno;
 152           return NSS_STATUS_TRYAGAIN;
 153         }
 154
 155       memcpy (__stpcpy (p, prefix), local_dir, local_dir_len + 1);
 156
 157       tablename_len = sizeof (prefix) - 1 + local_dir_len;
 158
 159       atomic_write_barrier ();
 160
 161       tablename_val = p;
 162     }
 163
 164   return NSS_STATUS_SUCCESS;
 165 }
 166
 167
 168 enum nss_status
 169 _nss_nisplus_setrpcent (int stayopen)
 170 {
 171   enum nss_status status = NSS_STATUS_SUCCESS;
 172
 173   __libc_lock_lock (lock);
 174
 175   if (result != NULL)
 176     {
 177       nis_freeresult (result);
 178       result = NULL;
 179     }
 180
 181   if (tablename_val == NULL)
 182     {
 183       int err;
 184       status = _nss_create_tablename (&err);
 185     }
 186
 187   __libc_lock_unlock (lock);
 188
 189   return status;
 190 }
 191
 192 enum nss_status
 193 _nss_nisplus_endrpcent (void)
 194 {
 195   __libc_lock_lock (lock);
 196
 197   if (result != NULL)
 198     {
 199       nis_freeresult (result);
 200       result = NULL;
 201     }
 202
 203   __libc_lock_unlock (lock);
 204
 205   return NSS_STATUS_SUCCESS;
 206 }
 207
 208 static enum nss_status
 209 internal_nisplus_getrpcent_r (struct rpcent *rpc, char *buffer,
 210                               size_t buflen, int *errnop)
 211 {
 212   int parse_res;
 213
 214   /* Get the next entry until we found a correct one. */
 215   do
 216     {
 217       nis_result *saved_res;
 218
 219       if (result == NULL)
 220         {
 221           saved_res = NULL;
 222           if (tablename_val == NULL)
 223             {
 224               enum nss_status status =  _nss_create_tablename (errnop);
 225
 226               if (status != NSS_STATUS_SUCCESS)
 227                 return status;
 228             }
 229
 230           result = nis_first_entry (tablename_val);
 231           if (result == NULL)
 232             {
 233               *errnop = errno;
 234               return NSS_STATUS_TRYAGAIN;
 235             }
 236           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 237             return niserr2nss (result->status);
 238         }
 239       else
 240         {
 241           saved_res = result;
 242           result = nis_next_entry (tablename_val, &result->cookie);
 243           if (result == NULL)
 244             {
 245               *errnop = errno;
 246               return NSS_STATUS_TRYAGAIN;
 247             }
 248           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 249             {
 250               nis_freeresult (saved_res);
 251               return niserr2nss (result->status);
 252             }
 253         }
 254
 255       parse_res = _nss_nisplus_parse_rpcent (result, rpc, buffer,
 256                                              buflen, errnop);
 257       if (parse_res == -1)
 258         {
 259           nis_freeresult (result);
 260           result = saved_res;
 261           *errnop = ERANGE;
 262           return NSS_STATUS_TRYAGAIN;
 263         }
 264       else
 265         {
 266           if (saved_res)
 267             nis_freeresult (saved_res);
 268         }
 269     }
 270   while (!parse_res);
 271
 272   return NSS_STATUS_SUCCESS;
 273 }
 274
 275 enum nss_status
 276 _nss_nisplus_getrpcent_r (struct rpcent *result, char *buffer,
 277                           size_t buflen, int *errnop)
 278 {
 279   int status;
 280
 281   __libc_lock_lock (lock);
 282
 283   status = internal_nisplus_getrpcent_r (result, buffer, buflen, errnop);
 284
 285   __libc_lock_unlock (lock);
 286
 287   return status;
 288 }
 289
 290 enum nss_status
 291 _nss_nisplus_getrpcbyname_r (const char *name, struct rpcent *rpc,
 292                              char *buffer, size_t buflen, int *errnop)
 293 {
 294   int parse_res;
 295
 296   if (tablename_val == NULL)
 297     {
 298       __libc_lock_lock (lock);
 299
 300       enum nss_status status = _nss_create_tablename (errnop);
 301
 302       __libc_lock_unlock (lock);
 303
 304       if (status != NSS_STATUS_SUCCESS)
 305         return status;
 306     }
 307
 308   if (name == NULL)
 309     return NSS_STATUS_NOTFOUND;
 310
 311   char buf[strlen (name) + 10 + tablename_len];
 312   int olderr = errno;
 313
 314   /* Search at first in the alias list, and use the correct name
 315      for the next search */
 316   snprintf (buf, sizeof (buf), "[name=%s],%s", name, tablename_val);
 317   nis_result *result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS | USE_DGRAM,
 318                                  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 | USE_DGRAM,
 346                          NULL, NULL);
 347     }
 348
 349   if (result == NULL)
 350     {
 351       *errnop = ENOMEM;
 352       return NSS_STATUS_TRYAGAIN;
 353     }
 354
 355   if (__builtin_expect (niserr2nss (result->status) != NSS_STATUS_SUCCESS, 0))
 356     {
 357       enum nss_status status = niserr2nss (result->status);
 358
 359       __set_errno (olderr);
 360
 361       nis_freeresult (result);
 362       return status;
 363     }
 364
 365   parse_res = _nss_nisplus_parse_rpcent (result, rpc, buffer, buflen,
 366                                              errnop);
 367
 368   nis_freeresult (result);
 369
 370   if (parse_res < 1)
 371     {
 372       if (parse_res == -1)
 373         {
 374           *errnop = ERANGE;
 375           return NSS_STATUS_TRYAGAIN;
 376         }
 377
 378       __set_errno (olderr);
 379       return NSS_STATUS_NOTFOUND;
 380     }
 381
 382   return NSS_STATUS_SUCCESS;
 383 }
 384
 385 enum nss_status
 386 _nss_nisplus_getrpcbynumber_r (const int number, struct rpcent *rpc,
 387                                char *buffer, size_t buflen, int *errnop)
 388 {
 389   if (tablename_val == NULL)
 390     {
 391       __libc_lock_lock (lock);
 392
 393       enum nss_status status = _nss_create_tablename (errnop);
 394
 395       __libc_lock_unlock (lock);
 396
 397       if (status != NSS_STATUS_SUCCESS)
 398         return status;
 399     }
 400
 401   char buf[12 + 3 * sizeof (number) + tablename_len];
 402   int olderr = errno;
 403
 404   snprintf (buf, sizeof (buf), "[number=%d],%s", number, tablename_val);
 405
 406   nis_result *result = nis_list (buf, FOLLOW_LINKS | FOLLOW_PATH | USE_DGRAM,
 407                                  NULL, NULL);
 408
 409   if (result == NULL)
 410     {
 411       *errnop = ENOMEM;
 412       return NSS_STATUS_TRYAGAIN;
 413     }
 414
 415   if (__builtin_expect (niserr2nss (result->status) != NSS_STATUS_SUCCESS,  0))
 416     {
 417       enum nss_status status = niserr2nss (result->status);
 418
 419       __set_errno (olderr);
 420
 421       nis_freeresult (result);
 422       return status;
 423     }
 424
 425   int parse_res = _nss_nisplus_parse_rpcent (result, rpc, buffer, buflen,
 426                                              errnop);
 427
 428   nis_freeresult (result);
 429
 430   if (parse_res < 1)
 431     {
 432       if (parse_res == -1)
 433         {
 434           *errnop = ERANGE;
 435           return NSS_STATUS_TRYAGAIN;
 436         }
 437       else
 438         {
 439           __set_errno (olderr);
 440           return NSS_STATUS_NOTFOUND;
 441         }
 442     }
 443
 444   return NSS_STATUS_SUCCESS;
 445 }