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 #ifdef PTR_DEMANGLE
 419       PTR_DEMANGLE (result);
 420 #endif
 421     }
 422   else
 423     {
 424       /* This name was not known before.  Now we have a node in the tree
 425          (in the proper sorted position for FCT_NAME) that points to
 426          &FCT_NAME instead of any real `known_function' structure.
 427          Allocate a new structure and fill it in.  */
 428
 429       known_function *known = malloc (sizeof *known);
 430       if (! known)
 431         {
 432         remove_from_tree:
 433           /* Oops.  We can't instantiate this node properly.
 434              Remove it from the tree.  */
 435           __tdelete (&fct_name, &ni->known, &known_compare);
 436           free (known);
 437           result = NULL;
 438         }
 439       else
 440         {
 441           /* Point the tree node at this new structure.  */
 442           *found = known;
 443           known->fct_name = fct_name;
 444
 445 #if !defined DO_STATIC_NSS || defined SHARED
 446           /* Load the appropriate library.  */
 447           if (nss_load_library (ni) != 0)
 448             /* This only happens when out of memory.  */
 449             goto remove_from_tree;
 450
 451           if (ni->library->lib_handle == (void *) -1l)
 452             /* Library not found => function not found.  */
 453             result = NULL;
 454           else
 455             {
 456               /* Get the desired function.  */
 457               size_t namlen = (5 + strlen (ni->name) + 1
 458                                + strlen (fct_name) + 1);
 459               char name[namlen];
 460
 461               /* Construct the function name.  */
 462               __stpcpy (__stpcpy (__stpcpy (__stpcpy (name, "_nss_"),
 463                                             ni->name),
 464                                   "_"),
 465                         fct_name);
 466
 467               /* Look up the symbol.  */
 468               result = __libc_dlsym (ni->library->lib_handle, name);
 469             }
 470 #else
 471           /* We can't get function address dynamically in static linking. */
 472           {
 473 # define DEFINE_ENT(h,nm)                                                     \
 474             { #h"_get"#nm"ent_r", _nss_##h##_get##nm##ent_r },                \
 475             { #h"_end"#nm"ent", _nss_##h##_end##nm##ent },                    \
 476             { #h"_set"#nm"ent", _nss_##h##_set##nm##ent },
 477 # define DEFINE_GET(h,nm)                                                     \
 478             { #h"_get"#nm"_r", _nss_##h##_get##nm##_r },
 479 # define DEFINE_GETBY(h,nm,ky)                                                \
 480             { #h"_get"#nm"by"#ky"_r", _nss_##h##_get##nm##by##ky##_r },
 481             static struct fct_tbl { const char *fname; void *fp; } *tp, tbl[] =
 482               {
 483 # include "function.def"
 484                 { NULL, NULL }
 485               };
 486             size_t namlen = (5 + strlen (ni->name) + 1
 487                              + strlen (fct_name) + 1);
 488             char name[namlen];
 489
 490             /* Construct the function name.  */
 491             __stpcpy (__stpcpy (__stpcpy (name, ni->name),
 492                                 "_"),
 493                       fct_name);
 494
 495             result = NULL;
 496             for (tp = &tbl[0]; tp->fname; tp++)
 497               if (strcmp (tp->fname, name) == 0)
 498                 {
 499                   result = tp->fp;
 500                   break;
 501                 }
 502           }
 503 #endif
 504
 505           /* Remember function pointer for later calls.  Even if null, we
 506              record it so a second try needn't search the library again.  */
 507           known->fct_ptr = result;
 508 #ifdef PTR_MANGLE
 509           PTR_MANGLE (known->fct_ptr);
 510 #endif
 511         }
 512     }
 513
 514   /* Remove the lock.  */
 515   __libc_lock_unlock (lock);
 516
 517   return result;
 518 }
 519 libc_hidden_def (__nss_lookup_function)
 520
 521
 522 static name_database *
 523 internal_function
 524 nss_parse_file (const char *fname)
 525 {
 526   FILE *fp;
 527   name_database *result;
 528   name_database_entry *last;
 529   char *line;
 530   size_t len;
 531
 532   /* Open the configuration file.  */
 533   fp = fopen (fname, "rce");
 534   if (fp == NULL)
 535     return NULL;
 536
 537   /* No threads use this stream.  */
 538   __fsetlocking (fp, FSETLOCKING_BYCALLER);
 539
 540   result = (name_database *) malloc (sizeof (name_database));
 541   if (result == NULL)
 542     {
 543       fclose (fp);
 544       return NULL;
 545     }
 546
 547   result->entry = NULL;
 548   result->library = NULL;
 549   last = NULL;
 550   line = NULL;
 551   len = 0;
 552   do
 553     {
 554       name_database_entry *this;
 555       ssize_t n;
 556
 557       n = __getline (&line, &len, fp);
 558       if (n < 0)
 559         break;
 560       if (line[n - 1] == '\n')
 561         line[n - 1] = '\0';
 562
 563       /* Because the file format does not know any form of quoting we
 564          can search forward for the next '#' character and if found
 565          make it terminating the line.  */
 566       *__strchrnul (line, '#') = '\0';
 567
 568       /* If the line is blank it is ignored.  */
 569       if (line[0] == '\0')
 570         continue;
 571
 572       /* Each line completely specifies the actions for a database.  */
 573       this = nss_getline (line);
 574       if (this != NULL)
 575         {
 576           if (last != NULL)
 577             last->next = this;
 578           else
 579             result->entry = this;
 580
 581           last = this;
 582         }
 583     }
 584   while (!feof_unlocked (fp));
 585
 586   /* Free the buffer.  */
 587   free (line);
 588   /* Close configuration file.  */
 589   fclose (fp);
 590
 591   return result;
 592 }
 593
 594
 595 /* Read the source names:
 596         `( <source> ( "[" "!"? (<status> "=" <action> )+ "]" )? )*'
 597    */
 598 static service_user *
 599 internal_function
 600 nss_parse_service_list (const char *line)
 601 {
 602   service_user *result = NULL, **nextp = &result;
 603
 604   while (1)
 605     {
 606       service_user *new_service;
 607       const char *name;
 608
 609       while (isspace (line[0]))
 610         ++line;
 611       if (line[0] == '\0')
 612         /* No source specified.  */
 613         return result;
 614
 615       /* Read <source> identifier.  */
 616       name = line;
 617       while (line[0] != '\0' && !isspace (line[0]) && line[0] != '[')
 618         ++line;
 619       if (name == line)
 620         return result;
 621
 622
 623       new_service = (service_user *) malloc (sizeof (service_user)
 624                                              + (line - name + 1));
 625       if (new_service == NULL)
 626         return result;
 627
 628       *((char *) __mempcpy (new_service->name, name, line - name)) = '\0';
 629
 630       /* Set default actions.  */
 631       new_service->actions[2 + NSS_STATUS_TRYAGAIN] = NSS_ACTION_CONTINUE;
 632       new_service->actions[2 + NSS_STATUS_UNAVAIL] = NSS_ACTION_CONTINUE;
 633       new_service->actions[2 + NSS_STATUS_NOTFOUND] = NSS_ACTION_CONTINUE;
 634       new_service->actions[2 + NSS_STATUS_SUCCESS] = NSS_ACTION_RETURN;
 635       new_service->actions[2 + NSS_STATUS_RETURN] = NSS_ACTION_RETURN;
 636       new_service->library = NULL;
 637       new_service->known = NULL;
 638       new_service->next = NULL;
 639
 640       while (isspace (line[0]))
 641         ++line;
 642
 643       if (line[0] == '[')
 644         {
 645           /* Read criterions.  */
 646           do
 647             ++line;
 648           while (line[0] != '\0' && isspace (line[0]));
 649
 650           do
 651             {
 652               int not;
 653               enum nss_status status;
 654               lookup_actions action;
 655
 656               /* Grok ! before name to mean all statii but that one.  */
 657               not = line[0] == '!';
 658               if (not)
 659                 ++line;
 660
 661               /* Read status name.  */
 662               name = line;
 663               while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
 664                      && line[0] != ']')
 665                 ++line;
 666
 667               /* Compare with known statii.  */
 668               if (line - name == 7)
 669                 {
 670                   if (__strncasecmp (name, "SUCCESS", 7) == 0)
 671                     status = NSS_STATUS_SUCCESS;
 672                   else if (__strncasecmp (name, "UNAVAIL", 7) == 0)
 673                     status = NSS_STATUS_UNAVAIL;
 674                   else
 675                     goto finish;
 676                 }
 677               else if (line - name == 8)
 678                 {
 679                   if (__strncasecmp (name, "NOTFOUND", 8) == 0)
 680                     status = NSS_STATUS_NOTFOUND;
 681                   else if (__strncasecmp (name, "TRYAGAIN", 8) == 0)
 682                     status = NSS_STATUS_TRYAGAIN;
 683                   else
 684                     goto finish;
 685                 }
 686               else
 687                 goto finish;
 688
 689               while (isspace (line[0]))
 690                 ++line;
 691               if (line[0] != '=')
 692                 goto finish;
 693               do
 694                 ++line;
 695               while (isspace (line[0]));
 696
 697               name = line;
 698               while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
 699                      && line[0] != ']')
 700                 ++line;
 701
 702               if (line - name == 6 && __strncasecmp (name, "RETURN", 6) == 0)
 703                 action = NSS_ACTION_RETURN;
 704               else if (line - name == 8
 705                        && __strncasecmp (name, "CONTINUE", 8) == 0)
 706                 action = NSS_ACTION_CONTINUE;
 707               else
 708                 goto finish;
 709
 710               if (not)
 711                 {
 712                   /* Save the current action setting for this status,
 713                      set them all to the given action, and reset this one.  */
 714                   const lookup_actions save = new_service->actions[2 + status];
 715                   new_service->actions[2 + NSS_STATUS_TRYAGAIN] = action;
 716                   new_service->actions[2 + NSS_STATUS_UNAVAIL] = action;
 717                   new_service->actions[2 + NSS_STATUS_NOTFOUND] = action;
 718                   new_service->actions[2 + NSS_STATUS_SUCCESS] = action;
 719                   new_service->actions[2 + status] = save;
 720                 }
 721               else
 722                 new_service->actions[2 + status] = action;
 723
 724               /* Skip white spaces.  */
 725               while (isspace (line[0]))
 726                 ++line;
 727             }
 728           while (line[0] != ']');
 729
 730           /* Skip the ']'.  */
 731           ++line;
 732         }
 733
 734       *nextp = new_service;
 735       nextp = &new_service->next;
 736       continue;
 737
 738     finish:
 739       free (new_service);
 740       return result;
 741     }
 742 }
 743
 744 static name_database_entry *
 745 internal_function
 746 nss_getline (char *line)
 747 {
 748   const char *name;
 749   name_database_entry *result;
 750   size_t len;
 751
 752   /* Ignore leading white spaces.  ATTENTION: this is different from
 753      what is implemented in Solaris.  The Solaris man page says a line
 754      beginning with a white space character is ignored.  We regard
 755      this as just another misfeature in Solaris.  */
 756   while (isspace (line[0]))
 757     ++line;
 758
 759   /* Recognize `<database> ":"'.  */
 760   name = line;
 761   while (line[0] != '\0' && !isspace (line[0]) && line[0] != ':')
 762     ++line;
 763   if (line[0] == '\0' || name == line)
 764     /* Syntax error.  */
 765     return NULL;
 766   *line++ = '\0';
 767
 768   len = strlen (name) + 1;
 769
 770   result = (name_database_entry *) malloc (sizeof (name_database_entry) + len);
 771   if (result == NULL)
 772     return NULL;
 773
 774   /* Save the database name.  */
 775   memcpy (result->name, name, len);
 776
 777   /* Parse the list of services.  */
 778   result->service = nss_parse_service_list (line);
 779
 780   result->next = NULL;
 781   return result;
 782 }
 783
 784
 785 static service_library *
 786 internal_function
 787 nss_new_service (name_database *database, const char *name)
 788 {
 789   service_library **currentp = &database->library;
 790
 791   while (*currentp != NULL)
 792     {
 793       if (strcmp ((*currentp)->name, name) == 0)
 794         return *currentp;
 795       currentp = &(*currentp)->next;
 796     }
 797
 798   /* We have to add the new service.  */
 799   *currentp = (service_library *) malloc (sizeof (service_library));
 800   if (*currentp == NULL)
 801     return NULL;
 802
 803   (*currentp)->name = name;
 804   (*currentp)->lib_handle = NULL;
 805   (*currentp)->next = NULL;
 806
 807   return *currentp;
 808 }
 809
 810
 811 #ifdef SHARED
 812 /* Load all libraries for the service.  */
 813 static void
 814 nss_load_all_libraries (const char *service, const char *def)
 815 {
 816   service_user *ni = NULL;
 817
 818   if (__nss_database_lookup (service, NULL, def, &ni) == 0)
 819     while (ni != NULL)
 820       {
 821         nss_load_library (ni);
 822         ni = ni->next;
 823       }
 824 }
 825
 826
 827 /* Called by nscd and nscd alone.  */
 828 void
 829 __nss_disable_nscd (void (*cb) (size_t, struct traced_file *))
 830 {
 831 # ifdef PTR_MANGLE
 832   PTR_MANGLE (cb);
 833 # endif
 834   nscd_init_cb = cb;
 835   is_nscd = true;
 836
 837   /* Find all the relevant modules so that the init functions are called.  */
 838   nss_load_all_libraries ("passwd", "compat [NOTFOUND=return] files");
 839   nss_load_all_libraries ("group", "compat [NOTFOUND=return] files");
 840   nss_load_all_libraries ("hosts", "dns [!UNAVAIL=return] files");
 841   nss_load_all_libraries ("services", NULL);
 842
 843   /* Disable all uses of NSCD.  */
 844   __nss_not_use_nscd_passwd = -1;
 845   __nss_not_use_nscd_group = -1;
 846   __nss_not_use_nscd_hosts = -1;
 847   __nss_not_use_nscd_services = -1;
 848   __nss_not_use_nscd_netgroup = -1;
 849 }
 850 #endif
 851
 852 static void
 853 free_database_entries (name_database_entry *entry)
 854 {
 855   while (entry != NULL)
 856     {
 857       name_database_entry *olde = entry;
 858       service_user *service = entry->service;
 859
 860       while (service != NULL)
 861         {
 862           service_user *olds = service;
 863
 864           if (service->known != NULL)
 865             __tdestroy (service->known, free);
 866
 867           service = service->next;
 868           free (olds);
 869         }
 870
 871       entry = entry->next;
 872       free (olde);
 873     }
 874 }
 875
 876 /* Free all resources if necessary.  */
 877 libc_freeres_fn (free_defconfig)
 878 {
 879   name_database_entry *entry = defconfig_entries;
 880
 881   if (entry == NULL)
 882     /* defconfig was not used.  */
 883     return;
 884
 885   /* Don't disturb ongoing other threads (if there are any).  */
 886   defconfig_entries = NULL;
 887
 888   free_database_entries (entry);
 889 }
 890
 891 libc_freeres_fn (free_mem)
 892 {
 893   name_database *top = service_table;
 894   service_library *library;
 895
 896   if (top == NULL)
 897     /* Maybe we have not read the nsswitch.conf file.  */
 898     return;
 899
 900   /* Don't disturb ongoing other threads (if there are any).  */
 901   service_table = NULL;
 902
 903   free_database_entries (top->entry);
 904
 905   library = top->library;
 906   while (library != NULL)
 907     {
 908       service_library *oldl = library;
 909
 910       if (library->lib_handle && library->lib_handle != (void *) -1l)
 911         __libc_dlclose (library->lib_handle);
 912
 913       library = library->next;
 914       free (oldl);
 915     }
 916
 917   free (top);
 918 }