nis/nss_nisplus/nisplus-service.c

   1 /* Copyright (C) 1997-1999,2001,2002,2003,2005 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Thorsten Kukuk <kukuk@suse.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 <string.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   ((res)->objects.objects_val[(idx)].EN_data.en_cols.en_cols_val[(col)].ec_value.ec_value_val)
  39
  40 #define NISENTRYLEN(idx,col,res) \
  41     ((res)->objects.objects_val[(idx)].EN_data.en_cols.en_cols_val[(col)].ec_value.ec_value_len)
  42
  43 static int
  44 _nss_nisplus_parse_servent (nis_result *result, struct servent *serv,
  45                             char *buffer, size_t buflen, int *errnop)
  46 {
  47   char *first_unused = buffer;
  48   size_t room_left = buflen;
  49
  50   if (result == NULL)
  51     return 0;
  52
  53   if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS)
  54       || __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ
  55       || strcmp (result->objects.objects_val->EN_data.en_type,
  56                  "services_tbl") != 0
  57       || result->objects.objects_val->EN_data.en_cols.en_cols_len < 4)
  58     return 0;
  59
  60   if (NISENTRYLEN (0, 0, result) >= room_left)
  61     {
  62     no_more_room:
  63       *errnop = ERANGE;
  64       return -1;
  65     }
  66   strncpy (first_unused, NISENTRYVAL (0, 0, result),
  67            NISENTRYLEN (0, 0, result));
  68   first_unused[NISENTRYLEN (0, 0, result)] = '\0';
  69   serv->s_name = first_unused;
  70   room_left -= (strlen (first_unused) +1);
  71   first_unused += strlen (first_unused) +1;
  72
  73   if (NISENTRYLEN (0, 2, result) >= room_left)
  74     goto no_more_room;
  75   strncpy (first_unused, NISENTRYVAL (0, 2, result),
  76            NISENTRYLEN (0, 2, result));
  77   first_unused[NISENTRYLEN (0, 2, result)] = '\0';
  78   serv->s_proto = first_unused;
  79   room_left -= strlen (first_unused) + 1;
  80   first_unused += strlen (first_unused) + 1;
  81
  82   serv->s_port = htons (atoi (NISENTRYVAL (0, 3, result)));
  83   char *p = first_unused;
  84
  85   char *line = p;
  86   for (unsigned int i = 0; i < result->objects.objects_len; ++i)
  87     {
  88       if (strcmp (NISENTRYVAL (i, 1, result), serv->s_name) != 0)
  89         {
  90           if (NISENTRYLEN (i, 1, result) + 2 > room_left)
  91             goto no_more_room;
  92           *p++ = ' ';
  93           p = __stpncpy (p, NISENTRYVAL (i, 1, result),
  94                          NISENTRYLEN (i, 1, result));
  95           *p = '\0';
  96           room_left -= (NISENTRYLEN (i, 1, result) + 1);
  97         }
  98     }
  99   *p++ = '\0';
 100   first_unused = p;
 101
 102   /* Adjust the pointer so it is aligned for
 103      storing pointers.  */
 104   first_unused += __alignof__ (char *) - 1;
 105   first_unused -= ((first_unused - (char *) 0) % __alignof__ (char *));
 106   serv->s_aliases = (char **) first_unused;
 107   if (room_left < sizeof (char *))
 108     goto no_more_room;
 109   room_left -= (sizeof (char *));
 110   serv->s_aliases[0] = NULL;
 111
 112   unsigned int 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       serv->s_aliases[i] = line;
 127
 128       while (*line != '\0' && *line != ' ')
 129         ++line;
 130
 131       if (*line == ' ')
 132         {
 133           *line = '\0';
 134           ++line;
 135           ++i;
 136         }
 137       else
 138         serv->s_aliases[i+1] = NULL;
 139     }
 140
 141   return 1;
 142 }
 143
 144 static enum nss_status
 145 _nss_create_tablename (int *errnop)
 146 {
 147   if (tablename_val == NULL)
 148     {
 149       const char *local_dir = nis_local_directory ();
 150       size_t local_dir_len = strlen (local_dir);
 151       static const char prefix[] = "services.org_dir.";
 152
 153       char *p = malloc (sizeof (prefix) + local_dir_len);
 154       if (tablename_val == NULL)
 155         {
 156           *errnop = errno;
 157           return NSS_STATUS_TRYAGAIN;
 158         }
 159
 160       memcpy (__stpcpy (p, prefix), local_dir, local_dir_len + 1);
 161
 162       tablename_len = sizeof (prefix) - 1 + local_dir_len;
 163
 164       atomic_write_barrier ();
 165
 166       tablename_val = p;
 167     }
 168
 169   return NSS_STATUS_SUCCESS;
 170 }
 171
 172
 173 enum nss_status
 174 _nss_nisplus_setservent (int stayopen)
 175 {
 176   enum nss_status status = NSS_STATUS_SUCCESS;
 177   int err;
 178
 179   __libc_lock_lock (lock);
 180
 181   if (result != NULL)
 182     {
 183       nis_freeresult (result);
 184       result = NULL;
 185     }
 186
 187   if (tablename_val == NULL)
 188     status = _nss_create_tablename (&err);
 189
 190   __libc_lock_unlock (lock);
 191
 192   return status;
 193 }
 194
 195 enum nss_status
 196 _nss_nisplus_endservent (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_getservent_r (struct servent *serv, char *buffer,
 213                                size_t buflen, int *errnop)
 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           if (tablename_val == NULL)
 226             {
 227               enum nss_status status = _nss_create_tablename (errnop);
 228
 229               if (status != NSS_STATUS_SUCCESS)
 230                 return status;
 231             }
 232
 233           result = nis_first_entry (tablename_val);
 234           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 235             return niserr2nss (result->status);
 236         }
 237       else
 238         {
 239           saved_res = result;
 240           result = nis_next_entry (tablename_val, &result->cookie);
 241           if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
 242             {
 243               nis_freeresult (saved_res);
 244               return niserr2nss (result->status);
 245             }
 246         }
 247
 248       parse_res = _nss_nisplus_parse_servent (result, serv, buffer,
 249                                               buflen, errnop);
 250       if (__builtin_expect (parse_res == -1, 0))
 251         {
 252           nis_freeresult (result);
 253           result = saved_res;
 254           *errnop = ERANGE;
 255           return NSS_STATUS_TRYAGAIN;
 256         }
 257       else
 258         {
 259           if (saved_res)
 260             nis_freeresult (saved_res);
 261         }
 262     }
 263   while (!parse_res);
 264
 265   return NSS_STATUS_SUCCESS;
 266 }
 267
 268 enum nss_status
 269 _nss_nisplus_getservent_r (struct servent *result, char *buffer,
 270                            size_t buflen, int *errnop)
 271 {
 272   __libc_lock_lock (lock);
 273
 274   int status = internal_nisplus_getservent_r (result, buffer, buflen, errnop);
 275
 276   __libc_lock_unlock (lock);
 277
 278   return status;
 279 }
 280
 281 enum nss_status
 282 _nss_nisplus_getservbyname_r (const char *name, const char *protocol,
 283                               struct servent *serv,
 284                               char *buffer, size_t buflen, int *errnop)
 285 {
 286   if (tablename_val == NULL)
 287     {
 288       __libc_lock_lock (lock);
 289
 290       enum nss_status status = _nss_create_tablename (errnop);
 291
 292       __libc_lock_unlock (lock);
 293
 294       if (status != NSS_STATUS_SUCCESS)
 295         return status;
 296     }
 297
 298   if (name == NULL || protocol == NULL)
 299     {
 300       *errnop = EINVAL;
 301       return NSS_STATUS_NOTFOUND;
 302     }
 303
 304   size_t protocol_len = strlen (protocol);
 305   char buf[strlen (name) + protocol_len + 17 + tablename_len];
 306   int olderr = errno;
 307
 308   /* Search at first in the alias list, and use the correct name
 309      for the next search */
 310   snprintf (buf, sizeof (buf), "[name=%s,proto=%s],%s", name, protocol,
 311             tablename_val);
 312   nis_result *result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 313
 314   if (result != NULL)
 315     {
 316       char *bufptr = buf;
 317
 318       /* If we did not find it, try it as original name. But if the
 319          database is correct, we should find it in the first case, too */
 320       if ((result->status != NIS_SUCCESS
 321            && result->status != NIS_S_SUCCESS)
 322           || __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ
 323           || strcmp (result->objects.objects_val->EN_data.en_type,
 324                      "services_tbl") != 0
 325           || result->objects.objects_val->EN_data.en_cols.en_cols_len < 4)
 326         snprintf (buf, sizeof (buf), "[cname=%s,proto=%s],%s", name, protocol,
 327                   tablename_val);
 328       else
 329         {
 330           /* We need to allocate a new buffer since there is no
 331              guarantee the returned name has a length limit.  */
 332           const char *entryval = NISENTRYVAL(0, 0, result);
 333           size_t buflen = (strlen (entryval) + protocol_len + 17
 334                            + tablename_len);
 335           bufptr = alloca (buflen);
 336           snprintf (bufptr, buflen, "[cname=%s,proto=%s],%s",
 337                     entryval, protocol, tablename_val);
 338         }
 339
 340       nis_freeresult (result);
 341       result = nis_list (bufptr, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 342     }
 343
 344   if (result == NULL)
 345     {
 346       *errnop = ENOMEM;
 347       return NSS_STATUS_TRYAGAIN;
 348     }
 349
 350   if (__builtin_expect (niserr2nss (result->status) != NSS_STATUS_SUCCESS, 0))
 351     {
 352       enum nss_status status = niserr2nss (result->status);
 353
 354       __set_errno (olderr);
 355
 356       nis_freeresult (result);
 357       return status;
 358     }
 359
 360   int parse_res = _nss_nisplus_parse_servent (result, serv, buffer, buflen,
 361                                               errnop);
 362   nis_freeresult (result);
 363
 364   if (__builtin_expect (parse_res < 1, 0))
 365     {
 366       if (parse_res == -1)
 367         {
 368           *errnop = ERANGE;
 369           return NSS_STATUS_TRYAGAIN;
 370         }
 371       else
 372         {
 373           __set_errno (olderr);
 374           return NSS_STATUS_NOTFOUND;
 375         }
 376     }
 377
 378   return NSS_STATUS_SUCCESS;
 379 }
 380
 381 enum nss_status
 382 _nss_nisplus_getservbyport_r (const int number, const char *protocol,
 383                               struct servent *serv,
 384                               char *buffer, size_t buflen, int *errnop)
 385 {
 386   if (tablename_val == NULL)
 387     {
 388       __libc_lock_lock (lock);
 389
 390       enum nss_status status = _nss_create_tablename (errnop);
 391
 392       __libc_lock_unlock (lock);
 393
 394       if (status != NSS_STATUS_SUCCESS)
 395         return status;
 396     }
 397
 398   if (protocol == NULL)
 399     {
 400       *errnop = EINVAL;
 401       return NSS_STATUS_NOTFOUND;
 402     }
 403
 404   char buf[17 + 3 * sizeof (int) + strlen (protocol) + tablename_len];
 405   int olderr = errno;
 406
 407   snprintf (buf, sizeof (buf), "[port=%d,proto=%s],%s",
 408             number, protocol, tablename_val);
 409
 410   nis_result *result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
 411
 412   if (result == NULL)
 413     {
 414       *errnop = ENOMEM;
 415       return NSS_STATUS_TRYAGAIN;
 416     }
 417
 418   if (__builtin_expect (niserr2nss (result->status) != NSS_STATUS_SUCCESS, 0))
 419     {
 420       enum nss_status status = niserr2nss (result->status);
 421
 422       __set_errno (olderr);
 423
 424       nis_freeresult (result);
 425       return status;
 426     }
 427
 428   int parse_res = _nss_nisplus_parse_servent (result, serv, buffer, buflen,
 429                                               errnop);
 430   nis_freeresult (result);
 431
 432   if (__builtin_expect (parse_res < 1, 0))
 433     {
 434       if (parse_res == -1)
 435         {
 436           *errnop = ERANGE;
 437           return NSS_STATUS_TRYAGAIN;
 438         }
 439       else
 440         {
 441           __set_errno (olderr);
 442           return NSS_STATUS_NOTFOUND;
 443         }
 444     }
 445
 446   return NSS_STATUS_SUCCESS;
 447 }