nis/nss_nisplus/nisplus-proto.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 <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_protoent (nis_result *result, struct protoent *proto,
  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
  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)->EN_data.en_type,
  59                  "protocols_tbl") != 0
  60       || NIS_RES_OBJECT (result)->EN_data.en_cols.en_cols_len < 3)
  61     return 0;
  62
  63   /* Generate the protocols entry format and use the normal parser */
  64   if (NISENTRYLEN (0, 0, result) + 1 > 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   proto->p_name = first_unused;
  74   size_t len = strlen (first_unused) + 1;
  75   room_left -= len;
  76   first_unused += len;
  77
  78
  79   proto->p_proto = atoi (NISENTRYVAL (0, 2, result));
  80
  81   /* XXX Rewrite at some point to allocate the array first and then
  82      copy the strings.  It wasteful to first concatenate the strings
  83      to just split them again later.  */
  84   char *line = first_unused;
  85   for (i = 0; i < NIS_RES_NUMOBJ (result); ++i)
  86     {
  87       if (strcmp (NISENTRYVAL (i, 1, result), proto->p_name) != 0)
  88         {
  89           if (NISENTRYLEN (i, 1, result) + 2 > room_left)
  90             goto no_more_room;
  91           *first_unused++ = ' ';
  92           first_unused = __stpncpy (first_unused, NISENTRYVAL (i, 1, result),
  93                                     NISENTRYLEN (i, 1, result));
  94           room_left -= NISENTRYLEN (i, 1, result) + 1;
  95         }
  96     }
  97   *first_unused++ = '\0';
  98
  99   /* Adjust the pointer so it is aligned for
 100      storing pointers.  */
 101   size_t adjust = ((__alignof__ (char *)
 102                     - (first_unused - (char *) 0) % __alignof__ (char *))
 103                    % __alignof__ (char *));
 104   if (room_left < adjust + sizeof (char *))
 105     goto no_more_room;
 106   first_unused += adjust;
 107   room_left -= adjust;
 108   proto->p_aliases = (char **) first_unused;
 109
 110   /* For the terminating NULL pointer.  */
 111   room_left -= sizeof (char *);
 112
 113   i = 0;
 114   while (*line != '\0')
 115     {
 116       /* Skip leading blanks.  */
 117       while (isspace (*line))
 118         line++;
 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       proto->p_aliases[i++] = line;
 127
 128       while (*line != '\0' && *line != ' ')
 129         ++line;
 130
 131       if (*line == ' ')
 132         *line++ = '\0';
 133     }
 134   proto->p_aliases[i] = NULL;
 135
 136   return 1;
 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[] = "protocols.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 enum nss_status
 168 _nss_nisplus_setprotoent (int stayopen)
 169 {
 170   enum nss_status status = NSS_STATUS_SUCCESS;
 171
 172   __libc_lock_lock (lock);
 173
 174   if (result != NULL)
 175     {
 176       nis_freeresult (result);
 177       result = NULL;
 178     }
 179
 180   if (tablename_val == NULL)
 181     {
 182       int err;
 183       status = _nss_create_tablename (&err);
 184     }
 185
 186   __libc_lock_unlock (lock);
 187
 188   return status;
 189 }
 190
 191 enum nss_status
 192 _nss_nisplus_endprotoent (void)
 193 {
 194   __libc_lock_lock (lock);
 195
 196   if (result != NULL)
 197     {
 198       nis_freeresult (result);
 199       result = NULL;
 200     }
 201
 202   __libc_lock_unlock (lock);
 203
 204   return NSS_STATUS_SUCCESS;
 205 }
 206
 207 static enum nss_status
 208 internal_nisplus_getprotoent_r (struct protoent *proto, char *buffer,
 209                                 size_t buflen, int *errnop)
 210 {
 211   int parse_res;
 212
 213   /* Get the next entry until we found a correct one. */
 214   do
 215     {
 216       nis_result *saved_res;
 217
 218       if (result == NULL)
 219         {
 220           saved_res = NULL;
 221           if (tablename_val == NULL)
 222             {
 223               enum nss_status status = _nss_create_tablename (errnop);
 224
 225               if (status != NSS_STATUS_SUCCESS)
 226                 return status;
 227             }
 228
 229           result = nis_first_entry (tablename_val);
 230           if (result == NULL)
 231             {
 232               *errnop = errno;
 233               return NSS_STATUS_TRYAGAIN;
 234             }
 235           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 236             return niserr2nss (result->status);
 237         }
 238       else
 239         {
 240           saved_res = result;
 241           result = nis_next_entry (tablename_val, &result->cookie);
 242           if (result == NULL)
 243             {
 244               *errnop = errno;
 245               return NSS_STATUS_TRYAGAIN;
 246             }
 247           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 248             {
 249               nis_freeresult (saved_res);
 250               return niserr2nss (result->status);
 251             }
 252         }
 253
 254       parse_res = _nss_nisplus_parse_protoent (result, proto, buffer,
 255                                                buflen, errnop);
 256       if (parse_res == -1)
 257         {
 258           nis_freeresult (result);
 259           result = saved_res;
 260           *errnop = ERANGE;
 261           return NSS_STATUS_TRYAGAIN;
 262         }
 263       else
 264         {
 265           if (saved_res)
 266             nis_freeresult (saved_res);
 267         }
 268     }
 269   while (!parse_res);
 270
 271   return NSS_STATUS_SUCCESS;
 272 }
 273
 274 enum nss_status
 275 _nss_nisplus_getprotoent_r (struct protoent *result, char *buffer,
 276                             size_t buflen, int *errnop)
 277 {
 278   int status;
 279
 280   __libc_lock_lock (lock);
 281
 282   status = internal_nisplus_getprotoent_r (result, buffer, buflen, errnop);
 283
 284   __libc_lock_unlock (lock);
 285
 286   return status;
 287 }
 288
 289 enum nss_status
 290 _nss_nisplus_getprotobyname_r (const char *name, struct protoent *proto,
 291                                char *buffer, size_t buflen, int *errnop)
 292 {
 293   int parse_res;
 294
 295   if (tablename_val == NULL)
 296     {
 297       __libc_lock_lock (lock);
 298
 299       enum nss_status status = _nss_create_tablename (errnop);
 300
 301       __libc_lock_unlock (lock);
 302
 303       if (status != NSS_STATUS_SUCCESS)
 304         return status;
 305     }
 306
 307   if (name == NULL)
 308     return NSS_STATUS_NOTFOUND;
 309
 310   char buf[strlen (name) + 10 + tablename_len];
 311   int olderr = errno;
 312
 313   /* Search at first in the alias list, and use the correct name
 314      for the next search */
 315   snprintf (buf, sizeof (buf), "[name=%s],%s", name, tablename_val);
 316   nis_result *result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 317
 318   if (result != NULL)
 319     {
 320       char *bufptr = buf;
 321
 322       /* If we did not find it, try it as original name. But if the
 323          database is correct, we should find it in the first case, too */
 324       if ((result->status != NIS_SUCCESS
 325            && result->status != NIS_S_SUCCESS)
 326           || __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ
 327           || strcmp (result->objects.objects_val->EN_data.en_type,
 328                          "protocols_tbl") != 0
 329           || result->objects.objects_val->EN_data.en_cols.en_cols_len < 3)
 330         snprintf (buf, sizeof (buf), "[cname=%s],%s", name, tablename_val);
 331       else
 332         {
 333           /* We need to allocate a new buffer since there is no
 334              guarantee the returned name has a length limit.  */
 335           const char *entryval = NISENTRYVAL (0, 0, result);
 336           size_t buflen = strlen (entryval) + 10 + tablename_len;
 337           bufptr = alloca (buflen);
 338           snprintf (bufptr, buflen, "[cname=%s],%s",
 339                     entryval, tablename_val);
 340         }
 341
 342       nis_freeresult (result);
 343       result = nis_list (bufptr, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 344     }
 345
 346   if (result == NULL)
 347     {
 348       __set_errno (ENOMEM);
 349       return NSS_STATUS_TRYAGAIN;
 350     }
 351
 352   if (__builtin_expect (niserr2nss (result->status) != NSS_STATUS_SUCCESS, 0))
 353     {
 354       enum nss_status status = niserr2nss (result->status);
 355
 356       __set_errno (olderr);
 357
 358       nis_freeresult (result);
 359       return status;
 360     }
 361
 362   parse_res = _nss_nisplus_parse_protoent (result, proto, buffer, buflen,
 363                                            errnop);
 364
 365   nis_freeresult (result);
 366
 367   if (parse_res < 1)
 368     {
 369       if (parse_res == -1)
 370         {
 371           *errnop = ERANGE;
 372           return NSS_STATUS_TRYAGAIN;
 373         }
 374       else
 375         {
 376           __set_errno (olderr);
 377           return NSS_STATUS_NOTFOUND;
 378         }
 379     }
 380
 381   return NSS_STATUS_SUCCESS;
 382 }
 383
 384 enum nss_status
 385 _nss_nisplus_getprotobynumber_r (const int number, struct protoent *proto,
 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       __set_errno (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_protoent (result, proto, 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 }