nss/nsswitch.c

   1 /* Copyright (C) 1996-2012 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
   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, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <ctype.h>
  20 #include <dlfcn.h>
  21 #include <errno.h>
  22 #include <netdb.h>
  23 #include <bits/libc-lock.h>
  24 #include <search.h>
  25 #include <stdio.h>
  26 #include <stdio_ext.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29
  30 #include <aliases.h>
  31 #include <grp.h>
  32 #include <netinet/ether.h>
  33 #include <pwd.h>
  34 #include <shadow.h>
  35
  36 #if !defined DO_STATIC_NSS || defined SHARED
  37 # include <gnu/lib-names.h>
  38 #endif
  39
  40 #include "nsswitch.h"
  41 #include "../nscd/nscd_proto.h"
  42 #include <sysdep.h>
  43
  44 /* Prototypes for the local functions.  */
  45 static name_database *nss_parse_file (const char *fname) internal_function;
  46 static name_database_entry *nss_getline (char *line) internal_function;
  47 static service_user *nss_parse_service_list (const char *line)
  48      internal_function;
  49 static service_library *nss_new_service (name_database *database,
  50                                          const char *name) internal_function;
  51
  52
  53 /* Declare external database variables.  */
  54 #define DEFINE_DATABASE(name)                                                 \
  55   extern service_user *__nss_##name##_database attribute_hidden;              \
  56   weak_extern (__nss_##name##_database)
  57 #include "databases.def"
  58 #undef DEFINE_DATABASE
  59
  60 /* Structure to map database name to variable.  */
  61 static const struct
  62 {
  63   const char name[10];
  64   service_user **dbp;
  65 } databases[] =
  66 {
  67 #define DEFINE_DATABASE(name)                                                 \
  68   { #name, &__nss_##name##_database },
  69 #include "databases.def"
  70 #undef DEFINE_DATABASE
  71 };
  72 #define ndatabases (sizeof (databases) / sizeof (databases[0]))
  73
  74 /* Flags whether custom rules for database is set.  */
  75 bool __nss_database_custom[NSS_DBSIDX_max];
  76
  77
  78 __libc_lock_define_initialized (static, lock)
  79
  80 #if !defined DO_STATIC_NSS || defined SHARED
  81 /* String with revision number of the shared object files.  */
  82 static const char *const __nss_shlib_revision = LIBNSS_FILES_SO + 15;
  83 #endif
  84
  85 /* The root of the whole data base.  */
  86 static name_database *service_table;
  87
  88 /* List of default service lists that were generated by glibc because
  89    /etc/nsswitch.conf did not provide a value.
  90    The list is only maintained so we can free such service lists in
  91    __libc_freeres.  */
  92 static name_database_entry *defconfig_entries;
  93
  94
  95 /* Nonzero if this is the nscd process.  */
  96 static bool is_nscd;
  97 /* The callback passed to the init functions when nscd is used.  */
  98 static void (*nscd_init_cb) (size_t, struct traced_file *);
  99
 100
 101 /* -1 == database not found
 102     0 == database entry pointer stored */
 103 int
 104 __nss_database_lookup (const char *database, const char *alternate_name,
 105                        const char *defconfig, service_user **ni)
 106 {
 107   /* Prevent multiple threads to change the service table.  */
 108   __libc_lock_lock (lock);
 109
 110   /* Reconsider database variable in case some other thread called
 111      `__nss_configure_lookup' while we waited for the lock.  */
 112   if (*ni != NULL)
 113     {
 114       __libc_lock_unlock (lock);
 115       return 0;
 116     }
 117
 118   /* Are we initialized yet?  */
 119   if (service_table == NULL)
 120     /* Read config file.  */
 121     service_table = nss_parse_file (_PATH_NSSWITCH_CONF);
 122
 123   /* Test whether configuration data is available.  */
 124   if (service_table != NULL)
 125     {
 126       /* Return first `service_user' entry for DATABASE.  */
 127       name_database_entry *entry;
 128
 129       /* XXX Could use some faster mechanism here.  But each database is
 130          only requested once and so this might not be critical.  */
 131       for (entry = service_table->entry; entry != NULL; entry = entry->next)
 132         if (strcmp (database, entry->name) == 0)
 133           *ni = entry->service;
 134
 135       if (*ni == NULL && alternate_name != NULL)
 136         /* We haven't found an entry so far.  Try to find it with the
 137            alternative name.  */
 138         for (entry = service_table->entry; entry != NULL; entry = entry->next)
 139           if (strcmp (alternate_name, entry->name) == 0)
 140             *ni = entry->service;
 141     }
 142
 143   /* No configuration data is available, either because nsswitch.conf
 144      doesn't exist or because it doesn't have a line for this database.
 145
 146      DEFCONFIG specifies the default service list for this database,
 147      or null to use the most common default.  */
 148   if (*ni == NULL)
 149     {
 150       *ni = nss_parse_service_list (defconfig
 151                                     ?: "nis [NOTFOUND=return] files");
 152       if (*ni != NULL)
 153         {
 154           /* Record the memory we've just allocated in defconfig_entries list,
 155              so we can free it later.  */
 156           name_database_entry *entry;
 157
 158           /* Allocate ENTRY plus size of name (1 here).  */
 159           entry = (name_database_entry *) malloc (sizeof (*entry) + 1);
 160
 161           if (entry != NULL)
 162             {
 163               entry->next = defconfig_entries;
 164               entry->service = *ni;
 165               entry->name[0] = '\0';
 166               defconfig_entries = entry;
 167             }
 168         }
 169     }
 170
 171   __libc_lock_unlock (lock);
 172
 173   return *ni != NULL ? 0 : -1;
 174 }
 175 libc_hidden_def (__nss_database_lookup)
 176
 177
 178 /* -1 == not found
 179     0 == function found
 180     1 == finished */
 181 int
 182 __nss_lookup (service_user **ni, const char *fct_name, const char *fct2_name,
 183               void **fctp)
 184 {
 185   *fctp = __nss_lookup_function (*ni, fct_name);
 186   if (*fctp == NULL && fct2_name != NULL)
 187     *fctp = __nss_lookup_function (*ni, fct2_name);
 188
 189   while (*fctp == NULL
 190          && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
 191          && (*ni)->next != NULL)
 192     {
 193       *ni = (*ni)->next;
 194
 195       *fctp = __nss_lookup_function (*ni, fct_name);
 196       if (*fctp == NULL && fct2_name != NULL)
 197         *fctp = __nss_lookup_function (*ni, fct2_name);
 198     }
 199
 200   return *fctp != NULL ? 0 : (*ni)->next == NULL ? 1 : -1;
 201 }
 202 libc_hidden_def (__nss_lookup)
 203
 204
 205 /* -1 == not found
 206     0 == adjusted for next function
 207     1 == finished */
 208 int
 209 __nss_next2 (service_user **ni, const char *fct_name, const char *fct2_name,
 210              void **fctp, int status, int all_values)
 211 {
 212   if (all_values)
 213     {
 214       if (nss_next_action (*ni, NSS_STATUS_TRYAGAIN) == NSS_ACTION_RETURN
 215           && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_RETURN
 216           && nss_next_action (*ni, NSS_STATUS_NOTFOUND) == NSS_ACTION_RETURN
 217           && nss_next_action (*ni, NSS_STATUS_SUCCESS) == NSS_ACTION_RETURN)
 218         return 1;
 219     }
 220   else
 221     {
 222       /* This is really only for debugging.  */
 223       if (__builtin_expect (NSS_STATUS_TRYAGAIN > status
 224                             || status > NSS_STATUS_RETURN, 0))
 225          __libc_fatal ("illegal status in __nss_next");
 226
 227        if (nss_next_action (*ni, status) == NSS_ACTION_RETURN)
 228          return 1;
 229     }
 230
 231   if ((*ni)->next == NULL)
 232     return -1;
 233
 234   do
 235     {
 236       *ni = (*ni)->next;
 237
 238       *fctp = __nss_lookup_function (*ni, fct_name);
 239       if (*fctp == NULL && fct2_name != NULL)
 240         *fctp = __nss_lookup_function (*ni, fct2_name);
 241     }
 242   while (*fctp == NULL
 243          && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
 244          && (*ni)->next != NULL);
 245
 246   return *fctp != NULL ? 0 : -1;
 247 }
 248 libc_hidden_def (__nss_next2)
 249
 250
 251 int
 252 attribute_compat_text_section
 253 __nss_next (service_user **ni, const char *fct_name, void **fctp, int status,
 254             int all_values)
 255 {
 256   return __nss_next2 (ni, fct_name, NULL, fctp, status, all_values);
 257 }
 258
 259
 260 int
 261 __nss_configure_lookup (const char *dbname, const char *service_line)
 262 {
 263   service_user *new_db;
 264   size_t cnt;
 265
 266   for (cnt = 0; cnt < ndatabases; ++cnt)
 267     {
 268       int cmp = strcmp (dbname, databases[cnt].name);
 269       if (cmp == 0)
 270         break;
 271       if (cmp < 0)
 272         {
 273           __set_errno (EINVAL);
 274           return -1;
 275         }
 276     }
 277
 278   if (cnt == ndatabases)
 279     {
 280       __set_errno (EINVAL);
 281       return -1;
 282     }
 283
 284   /* Test whether it is really used.  */
 285   if (databases[cnt].dbp == NULL)
 286     /* Nothing to do, but we could do.  */
 287     return 0;
 288
 289   /* Try to generate new data.  */
 290   new_db = nss_parse_service_list (service_line);
 291   if (new_db == NULL)
 292     {
 293       /* Illegal service specification.  */
 294       __set_errno (EINVAL);
 295       return -1;
 296     }
 297
 298   /* Prevent multiple threads to change the service table.  */
 299   __libc_lock_lock (lock);
 300
 301   /* Install new rules.  */
 302   *databases[cnt].dbp = new_db;
 303   __nss_database_custom[cnt] = true;
 304
 305   __libc_lock_unlock (lock);
 306
 307   return 0;
 308 }
 309
 310
 311 /* Comparison function for searching NI->known tree.  */
 312 static int
 313 known_compare (const void *p1, const void *p2)
 314 {
 315   return p1 == p2 ? 0 : strcmp (*(const char *const *) p1,
 316                                 *(const char *const *) p2);
 317 }
 318
 319
 320 #if !defined DO_STATIC_NSS || defined SHARED
 321 /* Load library.  */
 322 static int
 323 nss_load_library (service_user *ni)
 324 {
 325   if (ni->library == NULL)
 326     {
 327       /* This service has not yet been used.  Fetch the service
 328          library for it, creating a new one if need be.  If there
 329          is no service table from the file, this static variable
 330          holds the head of the service_library list made from the
 331          default configuration.  */
 332       static name_database default_table;
 333       ni->library = nss_new_service (service_table ?: &default_table,
 334                                      ni->name);
 335       if (ni->library == NULL)
 336         return -1;
 337     }
 338
 339   if (ni->library->lib_handle == NULL)
 340     {
 341       /* Load the shared library.  */
 342       size_t shlen = (7 + strlen (ni->name) + 3
 343                       + strlen (__nss_shlib_revision) + 1);
 344       int saved_errno = errno;
 345       char shlib_name[shlen];
 346
 347       /* Construct shared object name.  */
 348       __stpcpy (__stpcpy (__stpcpy (__stpcpy (shlib_name,
 349                                               "libnss_"),
 350                                     ni->name),
 351                           ".so"),
 352                 __nss_shlib_revision);
 353
 354       ni->library->lib_handle = __libc_dlopen (shlib_name);
 355       if (ni->library->lib_handle == NULL)
 356         {
 357           /* Failed to load the library.  */
 358           ni->library->lib_handle = (void *) -1l;
 359           __set_errno (saved_errno);
 360         }
 361       else if (is_nscd)
 362         {
 363           /* Call the init function when nscd is used.  */
 364           size_t initlen = (5 + strlen (ni->name)
 365                             + strlen ("_init") + 1);
 366           char init_name[initlen];
 367
 368           /* Construct the init function name.  */
 369           __stpcpy (__stpcpy (__stpcpy (init_name,
 370                                         "_nss_"),
 371                               ni->name),
 372                     "_init");
 373
 374           /* Find the optional init function.  */
 375           void (*ifct) (void (*) (size_t, struct traced_file *))
 376             = __libc_dlsym (ni->library->lib_handle, init_name);
 377           if (ifct != NULL)
 378             {
 379               void (*cb) (size_t, struct traced_file *) = nscd_init_cb;
 380 # ifdef PTR_DEMANGLE
 381               PTR_DEMANGLE (cb);
 382 # endif
 383               ifct (cb);
 384             }
 385         }
 386     }
 387
 388   return 0;
 389 }
 390 #endif
 391
 392
 393 void *
 394 __nss_lookup_function (service_user *ni, const char *fct_name)
 395 {
 396   void **found, *result;
 397
 398   /* We now modify global data.  Protect it.  */
 399   __libc_lock_lock (lock);
 400
 401   /* Search the tree of functions previously requested.  Data in the
 402      tree are `known_function' structures, whose first member is a
 403      `const char *', the lookup key.  The search returns a pointer to
 404      the tree node structure; the first member of the is a pointer to
 405      our structure (i.e. what will be a `known_function'); since the
 406      first member of that is the lookup key string, &FCT_NAME is close
 407      enough to a pointer to our structure to use as a lookup key that
 408      will be passed to `known_compare' (above).  */
 409
 410   found = __tsearch (&fct_name, &ni->known, &known_compare);
 411   if (found == NULL)
 412     /* This means out-of-memory.  */
 413     result = NULL;
 414   else if (*found != &fct_name)
 415     {
 416       /* The search found an existing structure in the tree.  */
 417       result = ((known_function *) *found)->fct_ptr;
 418       PTR_DEMANGLE (result);
 419     }
 420   else
 421     {
 422       /* This name was not known before.  Now we have a node in the tree
 423          (in the proper sorted position for FCT_NAME) that points to
 424          &FCT_NAME instead of any real `known_function' structure.
 425          Allocate a new structure and fill it in.  */
 426
 427       known_function *known = malloc (sizeof *known);
 428       if (! known)
 429         {
 430         remove_from_tree:
 431           /* Oops.  We can't instantiate this node properly.
 432              Remove it from the tree.  */
 433           __tdelete (&fct_name, &ni->known, &known_compare);
 434           free (known);
 435           result = NULL;
 436         }
 437       else
 438         {
 439           /* Point the tree node at this new structure.  */
 440           *found = known;
 441           known->fct_name = fct_name;
 442
 443 #if !defined DO_STATIC_NSS || defined SHARED
 444           /* Load the appropriate library.  */
 445           if (nss_load_library (ni) != 0)
 446             /* This only happens when out of memory.  */
 447             goto remove_from_tree;
 448
 449           if (ni->library->lib_handle == (void *) -1l)
 450             /* Library not found => function not found.  */
 451             result = NULL;
 452           else
 453             {
 454               /* Get the desired function.  */
 455               size_t namlen = (5 + strlen (ni->name) + 1
 456                                + strlen (fct_name) + 1);
 457               char name[namlen];
 458
 459               /* Construct the function name.  */
 460               __stpcpy (__stpcpy (__stpcpy (__stpcpy (name, "_nss_"),
 461                                             ni->name),
 462                                   "_"),
 463                         fct_name);
 464
 465               /* Look up the symbol.  */
 466               result = __libc_dlsym (ni->library->lib_handle, name);
 467             }
 468 #else
 469           /* We can't get function address dynamically in static linking. */
 470           {
 471 # define DEFINE_ENT(h,nm)                                                     \
 472             { #h"_get"#nm"ent_r", _nss_##h##_get##nm##ent_r },                \
 473             { #h"_end"#nm"ent", _nss_##h##_end##nm##ent },                    \
 474             { #h"_set"#nm"ent", _nss_##h##_set##nm##ent },
 475 # define DEFINE_GET(h,nm)                                                     \
 476             { #h"_get"#nm"_r", _nss_##h##_get##nm##_r },
 477 # define DEFINE_GETBY(h,nm,ky)                                                \
 478             { #h"_get"#nm"by"#ky"_r", _nss_##h##_get##nm##by##ky##_r },
 479             static struct fct_tbl { const char *fname; void *fp; } *tp, tbl[] =
 480               {
 481 # include "function.def"
 482                 { NULL, NULL }
 483               };
 484             size_t namlen = (5 + strlen (ni->name) + 1
 485                              + strlen (fct_name) + 1);
 486             char name[namlen];
 487
 488             /* Construct the function name.  */
 489             __stpcpy (__stpcpy (__stpcpy (name, ni->name),
 490                                 "_"),
 491                       fct_name);
 492
 493             result = NULL;
 494             for (tp = &tbl[0]; tp->fname; tp++)
 495               if (strcmp (tp->fname, name) == 0)
 496                 {
 497                   result = tp->fp;
 498                   break;
 499                 }
 500           }
 501 #endif
 502
 503           /* Remember function pointer for later calls.  Even if null, we
 504              record it so a second try needn't search the library again.  */
 505           known->fct_ptr = result;
 506           PTR_MANGLE (known->fct_ptr);
 507         }
 508     }
 509
 510   /* Remove the lock.  */
 511   __libc_lock_unlock (lock);
 512
 513   return result;
 514 }
 515 libc_hidden_def (__nss_lookup_function)
 516
 517
 518 static name_database *
 519 internal_function
 520 nss_parse_file (const char *fname)
 521 {
 522   FILE *fp;
 523   name_database *result;
 524   name_database_entry *last;
 525   char *line;
 526   size_t len;
 527
 528   /* Open the configuration file.  */
 529   fp = fopen (fname, "rce");
 530   if (fp == NULL)
 531     return NULL;
 532
 533   /* No threads use this stream.  */
 534   __fsetlocking (fp, FSETLOCKING_BYCALLER);
 535
 536   result = (name_database *) malloc (sizeof (name_database));
 537   if (result == NULL)
 538     {
 539       fclose (fp);
 540       return NULL;
 541     }
 542
 543   result->entry = NULL;
 544   result->library = NULL;
 545   last = NULL;
 546   line = NULL;
 547   len = 0;
 548   do
 549     {
 550       name_database_entry *this;
 551       ssize_t n;
 552
 553       n = __getline (&line, &len, fp);
 554       if (n < 0)
 555         break;
 556       if (line[n - 1] == '\n')
 557         line[n - 1] = '\0';
 558
 559       /* Because the file format does not know any form of quoting we
 560          can search forward for the next '#' character and if found
 561          make it terminating the line.  */
 562       *__strchrnul (line, '#') = '\0';
 563
 564       /* If the line is blank it is ignored.  */
 565       if (line[0] == '\0')
 566         continue;
 567
 568       /* Each line completely specifies the actions for a database.  */
 569       this = nss_getline (line);
 570       if (this != NULL)
 571         {
 572           if (last != NULL)
 573             last->next = this;
 574           else
 575             result->entry = this;
 576
 577           last = this;
 578         }
 579     }
 580   while (!feof_unlocked (fp));
 581
 582   /* Free the buffer.  */
 583   free (line);
 584   /* Close configuration file.  */
 585   fclose (fp);
 586
 587   return result;
 588 }
 589
 590
 591 /* Read the source names:
 592         `( <source> ( "[" "!"? (<status> "=" <action> )+ "]" )? )*'
 593    */
 594 static service_user *
 595 internal_function
 596 nss_parse_service_list (const char *line)
 597 {
 598   service_user *result = NULL, **nextp = &result;
 599
 600   while (1)
 601     {
 602       service_user *new_service;
 603       const char *name;
 604
 605       while (isspace (line[0]))
 606         ++line;
 607       if (line[0] == '\0')
 608         /* No source specified.  */
 609         return result;
 610
 611       /* Read <source> identifier.  */
 612       name = line;
 613       while (line[0] != '\0' && !isspace (line[0]) && line[0] != '[')
 614         ++line;
 615       if (name == line)
 616         return result;
 617
 618
 619       new_service = (service_user *) malloc (sizeof (service_user)
 620                                              + (line - name + 1));
 621       if (new_service == NULL)
 622         return result;
 623
 624       *((char *) __mempcpy (new_service->name, name, line - name)) = '\0';
 625
 626       /* Set default actions.  */
 627       new_service->actions[2 + NSS_STATUS_TRYAGAIN] = NSS_ACTION_CONTINUE;
 628       new_service->actions[2 + NSS_STATUS_UNAVAIL] = NSS_ACTION_CONTINUE;
 629       new_service->actions[2 + NSS_STATUS_NOTFOUND] = NSS_ACTION_CONTINUE;
 630       new_service->actions[2 + NSS_STATUS_SUCCESS] = NSS_ACTION_RETURN;
 631       new_service->actions[2 + NSS_STATUS_RETURN] = NSS_ACTION_RETURN;
 632       new_service->library = NULL;
 633       new_service->known = NULL;
 634       new_service->next = NULL;
 635
 636       while (isspace (line[0]))
 637         ++line;
 638
 639       if (line[0] == '[')
 640         {
 641           /* Read criterions.  */
 642           do
 643             ++line;
 644           while (line[0] != '\0' && isspace (line[0]));
 645
 646           do
 647             {
 648               int not;
 649               enum nss_status status;
 650               lookup_actions action;
 651
 652               /* Grok ! before name to mean all statii but that one.  */
 653               not = line[0] == '!';
 654               if (not)
 655                 ++line;
 656
 657               /* Read status name.  */
 658               name = line;
 659               while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
 660                      && line[0] != ']')
 661                 ++line;
 662
 663               /* Compare with known statii.  */
 664               if (line - name == 7)
 665                 {
 666                   if (__strncasecmp (name, "SUCCESS", 7) == 0)
 667                     status = NSS_STATUS_SUCCESS;
 668                   else if (__strncasecmp (name, "UNAVAIL", 7) == 0)
 669                     status = NSS_STATUS_UNAVAIL;
 670                   else
 671                     goto finish;
 672                 }
 673               else if (line - name == 8)
 674                 {
 675                   if (__strncasecmp (name, "NOTFOUND", 8) == 0)
 676                     status = NSS_STATUS_NOTFOUND;
 677                   else if (__strncasecmp (name, "TRYAGAIN", 8) == 0)
 678                     status = NSS_STATUS_TRYAGAIN;
 679                   else
 680                     goto finish;
 681                 }
 682               else
 683                 goto finish;
 684
 685               while (isspace (line[0]))
 686                 ++line;
 687               if (line[0] != '=')
 688                 goto finish;
 689               do
 690                 ++line;
 691               while (isspace (line[0]));
 692
 693               name = line;
 694               while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
 695                      && line[0] != ']')
 696                 ++line;
 697
 698               if (line - name == 6 && __strncasecmp (name, "RETURN", 6) == 0)
 699                 action = NSS_ACTION_RETURN;
 700               else if (line - name == 8
 701                        && __strncasecmp (name, "CONTINUE", 8) == 0)
 702                 action = NSS_ACTION_CONTINUE;
 703               else
 704                 goto finish;
 705
 706               if (not)
 707                 {
 708                   /* Save the current action setting for this status,
 709                      set them all to the given action, and reset this one.  */
 710                   const lookup_actions save = new_service->actions[2 + status];
 711                   new_service->actions[2 + NSS_STATUS_TRYAGAIN] = action;
 712                   new_service->actions[2 + NSS_STATUS_UNAVAIL] = action;
 713                   new_service->actions[2 + NSS_STATUS_NOTFOUND] = action;
 714                   new_service->actions[2 + NSS_STATUS_SUCCESS] = action;
 715                   new_service->actions[2 + status] = save;
 716                 }
 717               else
 718                 new_service->actions[2 + status] = action;
 719
 720               /* Skip white spaces.  */
 721               while (isspace (line[0]))
 722                 ++line;
 723             }
 724           while (line[0] != ']');
 725
 726           /* Skip the ']'.  */
 727           ++line;
 728         }
 729
 730       *nextp = new_service;
 731       nextp = &new_service->next;
 732       continue;
 733
 734     finish:
 735       free (new_service);
 736       return result;
 737     }
 738 }
 739
 740 static name_database_entry *
 741 internal_function
 742 nss_getline (char *line)
 743 {
 744   const char *name;
 745   name_database_entry *result;
 746   size_t len;
 747
 748   /* Ignore leading white spaces.  ATTENTION: this is different from
 749      what is implemented in Solaris.  The Solaris man page says a line
 750      beginning with a white space character is ignored.  We regard
 751      this as just another misfeature in Solaris.  */
 752   while (isspace (line[0]))
 753     ++line;
 754
 755   /* Recognize `<database> ":"'.  */
 756   name = line;
 757   while (line[0] != '\0' && !isspace (line[0]) && line[0] != ':')
 758     ++line;
 759   if (line[0] == '\0' || name == line)
 760     /* Syntax error.  */
 761     return NULL;
 762   *line++ = '\0';
 763
 764   len = strlen (name) + 1;
 765
 766   result = (name_database_entry *) malloc (sizeof (name_database_entry) + len);
 767   if (result == NULL)
 768     return NULL;
 769
 770   /* Save the database name.  */
 771   memcpy (result->name, name, len);
 772
 773   /* Parse the list of services.  */
 774   result->service = nss_parse_service_list (line);
 775
 776   result->next = NULL;
 777   return result;
 778 }
 779
 780
 781 static service_library *
 782 internal_function
 783 nss_new_service (name_database *database, const char *name)
 784 {
 785   service_library **currentp = &database->library;
 786
 787   while (*currentp != NULL)
 788     {
 789       if (strcmp ((*currentp)->name, name) == 0)
 790         return *currentp;
 791       currentp = &(*currentp)->next;
 792     }
 793
 794   /* We have to add the new service.  */
 795   *currentp = (service_library *) malloc (sizeof (service_library));
 796   if (*currentp == NULL)
 797     return NULL;
 798
 799   (*currentp)->name = name;
 800   (*currentp)->lib_handle = NULL;
 801   (*currentp)->next = NULL;
 802
 803   return *currentp;
 804 }
 805
 806
 807 #ifdef SHARED
 808 /* Load all libraries for the service.  */
 809 static void
 810 nss_load_all_libraries (const char *service, const char *def)
 811 {
 812   service_user *ni = NULL;
 813
 814   if (__nss_database_lookup (service, NULL, def, &ni) == 0)
 815     while (ni != NULL)
 816       {
 817         nss_load_library (ni);
 818         ni = ni->next;
 819       }
 820 }
 821
 822
 823 /* Called by nscd and nscd alone.  */
 824 void
 825 __nss_disable_nscd (void (*cb) (size_t, struct traced_file *))
 826 {
 827 # ifdef PTR_MANGLE
 828   PTR_MANGLE (cb);
 829 # endif
 830   nscd_init_cb = cb;
 831   is_nscd = true;
 832
 833   /* Find all the relevant modules so that the init functions are called.  */
 834   nss_load_all_libraries ("passwd", "compat [NOTFOUND=return] files");
 835   nss_load_all_libraries ("group", "compat [NOTFOUND=return] files");
 836   nss_load_all_libraries ("hosts", "dns [!UNAVAIL=return] files");
 837   nss_load_all_libraries ("services", NULL);
 838
 839   /* Disable all uses of NSCD.  */
 840   __nss_not_use_nscd_passwd = -1;
 841   __nss_not_use_nscd_group = -1;
 842   __nss_not_use_nscd_hosts = -1;
 843   __nss_not_use_nscd_services = -1;
 844   __nss_not_use_nscd_netgroup = -1;
 845 }
 846 #endif
 847
 848 static void
 849 free_database_entries (name_database_entry *entry)
 850 {
 851   while (entry != NULL)
 852     {
 853       name_database_entry *olde = entry;
 854       service_user *service = entry->service;
 855
 856       while (service != NULL)
 857         {
 858           service_user *olds = service;
 859
 860           if (service->known != NULL)
 861             __tdestroy (service->known, free);
 862
 863           service = service->next;
 864           free (olds);
 865         }
 866
 867       entry = entry->next;
 868       free (olde);
 869     }
 870 }
 871
 872 /* Free all resources if necessary.  */
 873 libc_freeres_fn (free_defconfig)
 874 {
 875   name_database_entry *entry = defconfig_entries;
 876
 877   if (entry == NULL)
 878     /* defconfig was not used.  */
 879     return;
 880
 881   /* Don't disturb ongoing other threads (if there are any).  */
 882   defconfig_entries = NULL;
 883
 884   free_database_entries (entry);
 885 }
 886
 887 libc_freeres_fn (free_mem)
 888 {
 889   name_database *top = service_table;
 890   service_library *library;
 891
 892   if (top == NULL)
 893     /* Maybe we have not read the nsswitch.conf file.  */
 894     return;
 895
 896   /* Don't disturb ongoing other threads (if there are any).  */
 897   service_table = NULL;
 898
 899   free_database_entries (top->entry);
 900
 901   library = top->library;
 902   while (library != NULL)
 903     {
 904       service_library *oldl = library;
 905
 906       if (library->lib_handle && library->lib_handle != (void *) -1l)
 907         __libc_dlclose (library->lib_handle);
 908
 909       library = library->next;
 910       free (oldl);
 911     }
 912
 913   free (top);
 914 }