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 #ifdef USE_NSCD
  96 /* Nonzero if this is the nscd process.  */
  97 static bool is_nscd;
  98 /* The callback passed to the init functions when nscd is used.  */
  99 static void (*nscd_init_cb) (size_t, struct traced_file *);
 100 #endif
 101
 102
 103 /* -1 == database not found
 104     0 == database entry pointer stored */
 105 int
 106 __nss_database_lookup (const char *database, const char *alternate_name,
 107                        const char *defconfig, service_user **ni)
 108 {
 109   /* Prevent multiple threads to change the service table.  */
 110   __libc_lock_lock (lock);
 111
 112   /* Reconsider database variable in case some other thread called
 113      `__nss_configure_lookup' while we waited for the lock.  */
 114   if (*ni != NULL)
 115     {
 116       __libc_lock_unlock (lock);
 117       return 0;
 118     }
 119
 120   /* Are we initialized yet?  */
 121   if (service_table == NULL)
 122     /* Read config file.  */
 123     service_table = nss_parse_file (_PATH_NSSWITCH_CONF);
 124
 125   /* Test whether configuration data is available.  */
 126   if (service_table != NULL)
 127     {
 128       /* Return first `service_user' entry for DATABASE.  */
 129       name_database_entry *entry;
 130
 131       /* XXX Could use some faster mechanism here.  But each database is
 132          only requested once and so this might not be critical.  */
 133       for (entry = service_table->entry; entry != NULL; entry = entry->next)
 134         if (strcmp (database, entry->name) == 0)
 135           *ni = entry->service;
 136
 137       if (*ni == NULL && alternate_name != NULL)
 138         /* We haven't found an entry so far.  Try to find it with the
 139            alternative name.  */
 140         for (entry = service_table->entry; entry != NULL; entry = entry->next)
 141           if (strcmp (alternate_name, entry->name) == 0)
 142             *ni = entry->service;
 143     }
 144
 145   /* No configuration data is available, either because nsswitch.conf
 146      doesn't exist or because it doesn't have a line for this database.
 147
 148      DEFCONFIG specifies the default service list for this database,
 149      or null to use the most common default.  */
 150   if (*ni == NULL)
 151     {
 152       *ni = nss_parse_service_list (defconfig
 153                                     ?: "nis [NOTFOUND=return] files");
 154       if (*ni != NULL)
 155         {
 156           /* Record the memory we've just allocated in defconfig_entries list,
 157              so we can free it later.  */
 158           name_database_entry *entry;
 159
 160           /* Allocate ENTRY plus size of name (1 here).  */
 161           entry = (name_database_entry *) malloc (sizeof (*entry) + 1);
 162
 163           if (entry != NULL)
 164             {
 165               entry->next = defconfig_entries;
 166               entry->service = *ni;
 167               entry->name[0] = '\0';
 168               defconfig_entries = entry;
 169             }
 170         }
 171     }
 172
 173   __libc_lock_unlock (lock);
 174
 175   return *ni != NULL ? 0 : -1;
 176 }
 177 libc_hidden_def (__nss_database_lookup)
 178
 179
 180 /* -1 == not found
 181     0 == function found
 182     1 == finished */
 183 int
 184 __nss_lookup (service_user **ni, const char *fct_name, const char *fct2_name,
 185               void **fctp)
 186 {
 187   *fctp = __nss_lookup_function (*ni, fct_name);
 188   if (*fctp == NULL && fct2_name != NULL)
 189     *fctp = __nss_lookup_function (*ni, fct2_name);
 190
 191   while (*fctp == NULL
 192          && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
 193          && (*ni)->next != NULL)
 194     {
 195       *ni = (*ni)->next;
 196
 197       *fctp = __nss_lookup_function (*ni, fct_name);
 198       if (*fctp == NULL && fct2_name != NULL)
 199         *fctp = __nss_lookup_function (*ni, fct2_name);
 200     }
 201
 202   return *fctp != NULL ? 0 : (*ni)->next == NULL ? 1 : -1;
 203 }
 204 libc_hidden_def (__nss_lookup)
 205
 206
 207 /* -1 == not found
 208     0 == adjusted for next function
 209     1 == finished */
 210 int
 211 __nss_next2 (service_user **ni, const char *fct_name, const char *fct2_name,
 212              void **fctp, int status, int all_values)
 213 {
 214   if (all_values)
 215     {
 216       if (nss_next_action (*ni, NSS_STATUS_TRYAGAIN) == NSS_ACTION_RETURN
 217           && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_RETURN
 218           && nss_next_action (*ni, NSS_STATUS_NOTFOUND) == NSS_ACTION_RETURN
 219           && nss_next_action (*ni, NSS_STATUS_SUCCESS) == NSS_ACTION_RETURN)
 220         return 1;
 221     }
 222   else
 223     {
 224       /* This is really only for debugging.  */
 225       if (__builtin_expect (NSS_STATUS_TRYAGAIN > status
 226                             || status > NSS_STATUS_RETURN, 0))
 227          __libc_fatal ("illegal status in __nss_next");
 228
 229        if (nss_next_action (*ni, status) == NSS_ACTION_RETURN)
 230          return 1;
 231     }
 232
 233   if ((*ni)->next == NULL)
 234     return -1;
 235
 236   do
 237     {
 238       *ni = (*ni)->next;
 239
 240       *fctp = __nss_lookup_function (*ni, fct_name);
 241       if (*fctp == NULL && fct2_name != NULL)
 242         *fctp = __nss_lookup_function (*ni, fct2_name);
 243     }
 244   while (*fctp == NULL
 245          && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
 246          && (*ni)->next != NULL);
 247
 248   return *fctp != NULL ? 0 : -1;
 249 }
 250 libc_hidden_def (__nss_next2)
 251
 252
 253 int
 254 attribute_compat_text_section
 255 __nss_next (service_user **ni, const char *fct_name, void **fctp, int status,
 256             int all_values)
 257 {
 258   return __nss_next2 (ni, fct_name, NULL, fctp, status, all_values);
 259 }
 260
 261
 262 int
 263 __nss_configure_lookup (const char *dbname, const char *service_line)
 264 {
 265   service_user *new_db;
 266   size_t cnt;
 267
 268   for (cnt = 0; cnt < ndatabases; ++cnt)
 269     {
 270       int cmp = strcmp (dbname, databases[cnt].name);
 271       if (cmp == 0)
 272         break;
 273       if (cmp < 0)
 274         {
 275           __set_errno (EINVAL);
 276           return -1;
 277         }
 278     }
 279
 280   if (cnt == ndatabases)
 281     {
 282       __set_errno (EINVAL);
 283       return -1;
 284     }
 285
 286   /* Test whether it is really used.  */
 287   if (databases[cnt].dbp == NULL)
 288     /* Nothing to do, but we could do.  */
 289     return 0;
 290
 291   /* Try to generate new data.  */
 292   new_db = nss_parse_service_list (service_line);
 293   if (new_db == NULL)
 294     {
 295       /* Illegal service specification.  */
 296       __set_errno (EINVAL);
 297       return -1;
 298     }
 299
 300   /* Prevent multiple threads to change the service table.  */
 301   __libc_lock_lock (lock);
 302
 303   /* Install new rules.  */
 304   *databases[cnt].dbp = new_db;
 305   __nss_database_custom[cnt] = true;
 306
 307   __libc_lock_unlock (lock);
 308
 309   return 0;
 310 }
 311
 312
 313 /* Comparison function for searching NI->known tree.  */
 314 static int
 315 known_compare (const void *p1, const void *p2)
 316 {
 317   return p1 == p2 ? 0 : strcmp (*(const char *const *) p1,
 318                                 *(const char *const *) p2);
 319 }
 320
 321
 322 #if !defined DO_STATIC_NSS || defined SHARED
 323 /* Load library.  */
 324 static int
 325 nss_load_library (service_user *ni)
 326 {
 327   if (ni->library == NULL)
 328     {
 329       /* This service has not yet been used.  Fetch the service
 330          library for it, creating a new one if need be.  If there
 331          is no service table from the file, this static variable
 332          holds the head of the service_library list made from the
 333          default configuration.  */
 334       static name_database default_table;
 335       ni->library = nss_new_service (service_table ?: &default_table,
 336                                      ni->name);
 337       if (ni->library == NULL)
 338         return -1;
 339     }
 340
 341   if (ni->library->lib_handle == NULL)
 342     {
 343       /* Load the shared library.  */
 344       size_t shlen = (7 + strlen (ni->name) + 3
 345                       + strlen (__nss_shlib_revision) + 1);
 346       int saved_errno = errno;
 347       char shlib_name[shlen];
 348
 349       /* Construct shared object name.  */
 350       __stpcpy (__stpcpy (__stpcpy (__stpcpy (shlib_name,
 351                                               "libnss_"),
 352                                     ni->name),
 353                           ".so"),
 354                 __nss_shlib_revision);
 355
 356       ni->library->lib_handle = __libc_dlopen (shlib_name);
 357       if (ni->library->lib_handle == NULL)
 358         {
 359           /* Failed to load the library.  */
 360           ni->library->lib_handle = (void *) -1l;
 361           __set_errno (saved_errno);
 362         }
 363 # ifdef USE_NSCD
 364       else if (is_nscd)
 365         {
 366           /* Call the init function when nscd is used.  */
 367           size_t initlen = (5 + strlen (ni->name)
 368                             + strlen ("_init") + 1);
 369           char init_name[initlen];
 370
 371           /* Construct the init function name.  */
 372           __stpcpy (__stpcpy (__stpcpy (init_name,
 373                                         "_nss_"),
 374                               ni->name),
 375                     "_init");
 376
 377           /* Find the optional init function.  */
 378           void (*ifct) (void (*) (size_t, struct traced_file *))
 379             = __libc_dlsym (ni->library->lib_handle, init_name);
 380           if (ifct != NULL)
 381             {
 382               void (*cb) (size_t, struct traced_file *) = nscd_init_cb;
 383 #  ifdef PTR_DEMANGLE
 384               PTR_DEMANGLE (cb);
 385 #  endif
 386               ifct (cb);
 387             }
 388         }
 389 # endif
 390     }
 391
 392   return 0;
 393 }
 394 #endif
 395
 396
 397 void *
 398 __nss_lookup_function (service_user *ni, const char *fct_name)
 399 {
 400   void **found, *result;
 401
 402   /* We now modify global data.  Protect it.  */
 403   __libc_lock_lock (lock);
 404
 405   /* Search the tree of functions previously requested.  Data in the
 406      tree are `known_function' structures, whose first member is a
 407      `const char *', the lookup key.  The search returns a pointer to
 408      the tree node structure; the first member of the is a pointer to
 409      our structure (i.e. what will be a `known_function'); since the
 410      first member of that is the lookup key string, &FCT_NAME is close
 411      enough to a pointer to our structure to use as a lookup key that
 412      will be passed to `known_compare' (above).  */
 413
 414   found = __tsearch (&fct_name, &ni->known, &known_compare);
 415   if (found == NULL)
 416     /* This means out-of-memory.  */
 417     result = NULL;
 418   else if (*found != &fct_name)
 419     {
 420       /* The search found an existing structure in the tree.  */
 421       result = ((known_function *) *found)->fct_ptr;
 422 #ifdef PTR_DEMANGLE
 423       PTR_DEMANGLE (result);
 424 #endif
 425     }
 426   else
 427     {
 428       /* This name was not known before.  Now we have a node in the tree
 429          (in the proper sorted position for FCT_NAME) that points to
 430          &FCT_NAME instead of any real `known_function' structure.
 431          Allocate a new structure and fill it in.  */
 432
 433       known_function *known = malloc (sizeof *known);
 434       if (! known)
 435         {
 436         remove_from_tree:
 437           /* Oops.  We can't instantiate this node properly.
 438              Remove it from the tree.  */
 439           __tdelete (&fct_name, &ni->known, &known_compare);
 440           free (known);
 441           result = NULL;
 442         }
 443       else
 444         {
 445           /* Point the tree node at this new structure.  */
 446           *found = known;
 447           known->fct_name = fct_name;
 448
 449 #if !defined DO_STATIC_NSS || defined SHARED
 450           /* Load the appropriate library.  */
 451           if (nss_load_library (ni) != 0)
 452             /* This only happens when out of memory.  */
 453             goto remove_from_tree;
 454
 455           if (ni->library->lib_handle == (void *) -1l)
 456             /* Library not found => function not found.  */
 457             result = NULL;
 458           else
 459             {
 460               /* Get the desired function.  */
 461               size_t namlen = (5 + strlen (ni->name) + 1
 462                                + strlen (fct_name) + 1);
 463               char name[namlen];
 464
 465               /* Construct the function name.  */
 466               __stpcpy (__stpcpy (__stpcpy (__stpcpy (name, "_nss_"),
 467                                             ni->name),
 468                                   "_"),
 469                         fct_name);
 470
 471               /* Look up the symbol.  */
 472               result = __libc_dlsym (ni->library->lib_handle, name);
 473             }
 474 #else
 475           /* We can't get function address dynamically in static linking. */
 476           {
 477 # define DEFINE_ENT(h,nm)                                                     \
 478             { #h"_get"#nm"ent_r", _nss_##h##_get##nm##ent_r },                \
 479             { #h"_end"#nm"ent", _nss_##h##_end##nm##ent },                    \
 480             { #h"_set"#nm"ent", _nss_##h##_set##nm##ent },
 481 # define DEFINE_GET(h,nm)                                                     \
 482             { #h"_get"#nm"_r", _nss_##h##_get##nm##_r },
 483 # define DEFINE_GETBY(h,nm,ky)                                                \
 484             { #h"_get"#nm"by"#ky"_r", _nss_##h##_get##nm##by##ky##_r },
 485             static struct fct_tbl { const char *fname; void *fp; } *tp, tbl[] =
 486               {
 487 # include "function.def"
 488                 { NULL, NULL }
 489               };
 490             size_t namlen = (5 + strlen (ni->name) + 1
 491                              + strlen (fct_name) + 1);
 492             char name[namlen];
 493
 494             /* Construct the function name.  */
 495             __stpcpy (__stpcpy (__stpcpy (name, ni->name),
 496                                 "_"),
 497                       fct_name);
 498
 499             result = NULL;
 500             for (tp = &tbl[0]; tp->fname; tp++)
 501               if (strcmp (tp->fname, name) == 0)
 502                 {
 503                   result = tp->fp;
 504                   break;
 505                 }
 506           }
 507 #endif
 508
 509           /* Remember function pointer for later calls.  Even if null, we
 510              record it so a second try needn't search the library again.  */
 511           known->fct_ptr = result;
 512 #ifdef PTR_MANGLE
 513           PTR_MANGLE (known->fct_ptr);
 514 #endif
 515         }
 516     }
 517
 518   /* Remove the lock.  */
 519   __libc_lock_unlock (lock);
 520
 521   return result;
 522 }
 523 libc_hidden_def (__nss_lookup_function)
 524
 525
 526 static name_database *
 527 internal_function
 528 nss_parse_file (const char *fname)
 529 {
 530   FILE *fp;
 531   name_database *result;
 532   name_database_entry *last;
 533   char *line;
 534   size_t len;
 535
 536   /* Open the configuration file.  */
 537   fp = fopen (fname, "rce");
 538   if (fp == NULL)
 539     return NULL;
 540
 541   /* No threads use this stream.  */
 542   __fsetlocking (fp, FSETLOCKING_BYCALLER);
 543
 544   result = (name_database *) malloc (sizeof (name_database));
 545   if (result == NULL)
 546     {
 547       fclose (fp);
 548       return NULL;
 549     }
 550
 551   result->entry = NULL;
 552   result->library = NULL;
 553   last = NULL;
 554   line = NULL;
 555   len = 0;
 556   do
 557     {
 558       name_database_entry *this;
 559       ssize_t n;
 560
 561       n = __getline (&line, &len, fp);
 562       if (n < 0)
 563         break;
 564       if (line[n - 1] == '\n')
 565         line[n - 1] = '\0';
 566
 567       /* Because the file format does not know any form of quoting we
 568          can search forward for the next '#' character and if found
 569          make it terminating the line.  */
 570       *__strchrnul (line, '#') = '\0';
 571
 572       /* If the line is blank it is ignored.  */
 573       if (line[0] == '\0')
 574         continue;
 575
 576       /* Each line completely specifies the actions for a database.  */
 577       this = nss_getline (line);
 578       if (this != NULL)
 579         {
 580           if (last != NULL)
 581             last->next = this;
 582           else
 583             result->entry = this;
 584
 585           last = this;
 586         }
 587     }
 588   while (!feof_unlocked (fp));
 589
 590   /* Free the buffer.  */
 591   free (line);
 592   /* Close configuration file.  */
 593   fclose (fp);
 594
 595   return result;
 596 }
 597
 598
 599 /* Read the source names:
 600         `( <source> ( "[" "!"? (<status> "=" <action> )+ "]" )? )*'
 601    */
 602 static service_user *
 603 internal_function
 604 nss_parse_service_list (const char *line)
 605 {
 606   service_user *result = NULL, **nextp = &result;
 607
 608   while (1)
 609     {
 610       service_user *new_service;
 611       const char *name;
 612
 613       while (isspace (line[0]))
 614         ++line;
 615       if (line[0] == '\0')
 616         /* No source specified.  */
 617         return result;
 618
 619       /* Read <source> identifier.  */
 620       name = line;
 621       while (line[0] != '\0' && !isspace (line[0]) && line[0] != '[')
 622         ++line;
 623       if (name == line)
 624         return result;
 625
 626
 627       new_service = (service_user *) malloc (sizeof (service_user)
 628                                              + (line - name + 1));
 629       if (new_service == NULL)
 630         return result;
 631
 632       *((char *) __mempcpy (new_service->name, name, line - name)) = '\0';
 633
 634       /* Set default actions.  */
 635       new_service->actions[2 + NSS_STATUS_TRYAGAIN] = NSS_ACTION_CONTINUE;
 636       new_service->actions[2 + NSS_STATUS_UNAVAIL] = NSS_ACTION_CONTINUE;
 637       new_service->actions[2 + NSS_STATUS_NOTFOUND] = NSS_ACTION_CONTINUE;
 638       new_service->actions[2 + NSS_STATUS_SUCCESS] = NSS_ACTION_RETURN;
 639       new_service->actions[2 + NSS_STATUS_RETURN] = NSS_ACTION_RETURN;
 640       new_service->library = NULL;
 641       new_service->known = NULL;
 642       new_service->next = NULL;
 643
 644       while (isspace (line[0]))
 645         ++line;
 646
 647       if (line[0] == '[')
 648         {
 649           /* Read criterions.  */
 650           do
 651             ++line;
 652           while (line[0] != '\0' && isspace (line[0]));
 653
 654           do
 655             {
 656               int not;
 657               enum nss_status status;
 658               lookup_actions action;
 659
 660               /* Grok ! before name to mean all statii but that one.  */
 661               not = line[0] == '!';
 662               if (not)
 663                 ++line;
 664
 665               /* Read status name.  */
 666               name = line;
 667               while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
 668                      && line[0] != ']')
 669                 ++line;
 670
 671               /* Compare with known statii.  */
 672               if (line - name == 7)
 673                 {
 674                   if (__strncasecmp (name, "SUCCESS", 7) == 0)
 675                     status = NSS_STATUS_SUCCESS;
 676                   else if (__strncasecmp (name, "UNAVAIL", 7) == 0)
 677                     status = NSS_STATUS_UNAVAIL;
 678                   else
 679                     goto finish;
 680                 }
 681               else if (line - name == 8)
 682                 {
 683                   if (__strncasecmp (name, "NOTFOUND", 8) == 0)
 684                     status = NSS_STATUS_NOTFOUND;
 685                   else if (__strncasecmp (name, "TRYAGAIN", 8) == 0)
 686                     status = NSS_STATUS_TRYAGAIN;
 687                   else
 688                     goto finish;
 689                 }
 690               else
 691                 goto finish;
 692
 693               while (isspace (line[0]))
 694                 ++line;
 695               if (line[0] != '=')
 696                 goto finish;
 697               do
 698                 ++line;
 699               while (isspace (line[0]));
 700
 701               name = line;
 702               while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
 703                      && line[0] != ']')
 704                 ++line;
 705
 706               if (line - name == 6 && __strncasecmp (name, "RETURN", 6) == 0)
 707                 action = NSS_ACTION_RETURN;
 708               else if (line - name == 8
 709                        && __strncasecmp (name, "CONTINUE", 8) == 0)
 710                 action = NSS_ACTION_CONTINUE;
 711               else
 712                 goto finish;
 713
 714               if (not)
 715                 {
 716                   /* Save the current action setting for this status,
 717                      set them all to the given action, and reset this one.  */
 718                   const lookup_actions save = new_service->actions[2 + status];
 719                   new_service->actions[2 + NSS_STATUS_TRYAGAIN] = action;
 720                   new_service->actions[2 + NSS_STATUS_UNAVAIL] = action;
 721                   new_service->actions[2 + NSS_STATUS_NOTFOUND] = action;
 722                   new_service->actions[2 + NSS_STATUS_SUCCESS] = action;
 723                   new_service->actions[2 + status] = save;
 724                 }
 725               else
 726                 new_service->actions[2 + status] = action;
 727
 728               /* Skip white spaces.  */
 729               while (isspace (line[0]))
 730                 ++line;
 731             }
 732           while (line[0] != ']');
 733
 734           /* Skip the ']'.  */
 735           ++line;
 736         }
 737
 738       *nextp = new_service;
 739       nextp = &new_service->next;
 740       continue;
 741
 742     finish:
 743       free (new_service);
 744       return result;
 745     }
 746 }
 747
 748 static name_database_entry *
 749 internal_function
 750 nss_getline (char *line)
 751 {
 752   const char *name;
 753   name_database_entry *result;
 754   size_t len;
 755
 756   /* Ignore leading white spaces.  ATTENTION: this is different from
 757      what is implemented in Solaris.  The Solaris man page says a line
 758      beginning with a white space character is ignored.  We regard
 759      this as just another misfeature in Solaris.  */
 760   while (isspace (line[0]))
 761     ++line;
 762
 763   /* Recognize `<database> ":"'.  */
 764   name = line;
 765   while (line[0] != '\0' && !isspace (line[0]) && line[0] != ':')
 766     ++line;
 767   if (line[0] == '\0' || name == line)
 768     /* Syntax error.  */
 769     return NULL;
 770   *line++ = '\0';
 771
 772   len = strlen (name) + 1;
 773
 774   result = (name_database_entry *) malloc (sizeof (name_database_entry) + len);
 775   if (result == NULL)
 776     return NULL;
 777
 778   /* Save the database name.  */
 779   memcpy (result->name, name, len);
 780
 781   /* Parse the list of services.  */
 782   result->service = nss_parse_service_list (line);
 783
 784   result->next = NULL;
 785   return result;
 786 }
 787
 788
 789 static service_library *
 790 internal_function
 791 nss_new_service (name_database *database, const char *name)
 792 {
 793   service_library **currentp = &database->library;
 794
 795   while (*currentp != NULL)
 796     {
 797       if (strcmp ((*currentp)->name, name) == 0)
 798         return *currentp;
 799       currentp = &(*currentp)->next;
 800     }
 801
 802   /* We have to add the new service.  */
 803   *currentp = (service_library *) malloc (sizeof (service_library));
 804   if (*currentp == NULL)
 805     return NULL;
 806
 807   (*currentp)->name = name;
 808   (*currentp)->lib_handle = NULL;
 809   (*currentp)->next = NULL;
 810
 811   return *currentp;
 812 }
 813
 814
 815 #if defined SHARED && defined USE_NSCD
 816 /* Load all libraries for the service.  */
 817 static void
 818 nss_load_all_libraries (const char *service, const char *def)
 819 {
 820   service_user *ni = NULL;
 821
 822   if (__nss_database_lookup (service, NULL, def, &ni) == 0)
 823     while (ni != NULL)
 824       {
 825         nss_load_library (ni);
 826         ni = ni->next;
 827       }
 828 }
 829
 830
 831 /* Called by nscd and nscd alone.  */
 832 void
 833 __nss_disable_nscd (void (*cb) (size_t, struct traced_file *))
 834 {
 835 # ifdef PTR_MANGLE
 836   PTR_MANGLE (cb);
 837 # endif
 838   nscd_init_cb = cb;
 839   is_nscd = true;
 840
 841   /* Find all the relevant modules so that the init functions are called.  */
 842   nss_load_all_libraries ("passwd", "compat [NOTFOUND=return] files");
 843   nss_load_all_libraries ("group", "compat [NOTFOUND=return] files");
 844   nss_load_all_libraries ("hosts", "dns [!UNAVAIL=return] files");
 845   nss_load_all_libraries ("services", NULL);
 846
 847   /* Disable all uses of NSCD.  */
 848   __nss_not_use_nscd_passwd = -1;
 849   __nss_not_use_nscd_group = -1;
 850   __nss_not_use_nscd_hosts = -1;
 851   __nss_not_use_nscd_services = -1;
 852   __nss_not_use_nscd_netgroup = -1;
 853 }
 854 #endif
 855
 856 static void
 857 free_database_entries (name_database_entry *entry)
 858 {
 859   while (entry != NULL)
 860     {
 861       name_database_entry *olde = entry;
 862       service_user *service = entry->service;
 863
 864       while (service != NULL)
 865         {
 866           service_user *olds = service;
 867
 868           if (service->known != NULL)
 869             __tdestroy (service->known, free);
 870
 871           service = service->next;
 872           free (olds);
 873         }
 874
 875       entry = entry->next;
 876       free (olde);
 877     }
 878 }
 879
 880 /* Free all resources if necessary.  */
 881 libc_freeres_fn (free_defconfig)
 882 {
 883   name_database_entry *entry = defconfig_entries;
 884
 885   if (entry == NULL)
 886     /* defconfig was not used.  */
 887     return;
 888
 889   /* Don't disturb ongoing other threads (if there are any).  */
 890   defconfig_entries = NULL;
 891
 892   free_database_entries (entry);
 893 }
 894
 895 libc_freeres_fn (free_mem)
 896 {
 897   name_database *top = service_table;
 898   service_library *library;
 899
 900   if (top == NULL)
 901     /* Maybe we have not read the nsswitch.conf file.  */
 902     return;
 903
 904   /* Don't disturb ongoing other threads (if there are any).  */
 905   service_table = NULL;
 906
 907   free_database_entries (top->entry);
 908
 909   library = top->library;
 910   while (library != NULL)
 911     {
 912       service_library *oldl = library;
 913
 914       if (library->lib_handle && library->lib_handle != (void *) -1l)
 915         __libc_dlclose (library->lib_handle);
 916
 917       library = library->next;
 918       free (oldl);
 919     }
 920
 921   free (top);
 922 }